Organic electronic material, ink composition containing same, and organic thin film, organic electronic element, organic eletroluminescent element, lighting device, and display device formed therewith

ABSTRACT

Provided are: an organic electronic material which can be easily multilayered and that can be used in substrates, such as resin, that cannot be processed at high temperatures; an ink composition containing the same; an organic thin film formed using said organic electronic material or said ink composition; and an organic electronic element and an organic EL element that are formed using said organic thin film and that have a superior luminous efficacy and emission lifespan than conventional elements. Specifically, provided are: an organic electronic material that is characterized by containing an oligomer or a polymer having a structure that branches into three or more directions and has at least one polymerizable substituent; an ink composition containing said organic electronic material; and an organic thin film prepared using the aforementioned organic electronic material. Further, provided are an organic electronic element and an organic electroluminescent element containing said organic thin film.

TECHNICAL FIELD

The present invention relates to an organic electronic material and anink composition containing the material, and an organic thin film, anorganic electronic element, an organic electroluminescent element(hereinafter, also referred to as organic EL element), a lighting deviceand a display device, all of which use the organic electronic materialand the ink composition.

BACKGROUND ART

Organic electronic elements are elements that carry out an electricaloperation using organic substances, and are expected to exhibit featuressuch as energy saving, low price, and flexibility. Thus, more attentionis being paid to organic electronic elements as a technology replacingthe traditional inorganic semiconductors that are mainly composed ofsilicon.

Examples of the organic electronic elements include organic EL elements,organic transistors, and organic solar cells.

Among the organic electronic elements, the organic EL elements areattracting attention for their use as, for example, large-sized solidstate light sources as a substitute for incandescent lamps andgas-filled lamps. Furthermore, the organic EL elements are alsoreceiving attention as the most promising self-emissive displayssubstituting for liquid crystal displays (LCD) in the field of flatpanel display (FPD), and thus, productization of the organic EL elementsis in progress.

The organic EL elements are largely classified into two classes such aslow molecular weight type organic EL elements and polymer type organicEL elements, on the basis of the material used and the film formingmethod. The polymer type organic EL elements are such that since theorganic material is composed of a polymeric material, film formation canbe conveniently achieved during printing, inkjetting or the like ascompared with the low molecular weight type organic EL elements whichrequire a vacuum system for film formation, and therefore, the polymertype organic EL elements are elements indispensable for large-sizedorganic EL displays of the future.

Vigorous research has been conducted so far on the low molecular weighttype organic EL elements and the polymer type organic EL elements, butthere still are problems of low light emission efficiency and a shortelement lifetime. As a means to address these problems, the lowmolecular weight type organic EL elements are fabricated to have amultilayer structure.

FIG. 1 shows an example of a multilayered organic EL element. In FIG. 1,a layer which is in charge of light emission is indicated as a lightemitting layer 1, and in case that the organic EL element has otherlayers, a layer that is in contact with an anode 2 is indicated as ahole injection layer 3, while a layer that is in contact with a cathode4 is indicated as an electron injection layer 5. Furthermore, if anotherlayer is present between the light emitting layer 1 and the holeinjection layer 3, the layer is indicated as a hole transport layer 6.If another layer is present between the light emitting layer 1 and theelectron injection layer 5, the layer is indicated as an electrontransport layer 7. In FIG. 1, reference numeral 8 indicates a substrate.

Since film formation during the production of low molecular weight typeorganic EL elements is dominantly carried out by a vapor depositionmethod, a multilayer structure can be easily achieved by performingvapor deposition while sequentially changing the compounds used. On theother hand, in the case of the polymer type organic EL elements, sincefilm formation is carried out using a wet process such as printing orinkjetting, there occurs a problem that when an upper layer is applied,the lower layer undergoes dissolution.

Therefore, providing a multilayer structure in the polymer type organicEL elements is more difficult than in the case of the low molecularweight type organic EL elements, and the effects of enhancing the lightemission efficiency and improving the lifetime could not be obtained.

In order to cope with this problem, several methods have been hithertosuggested. One of them is a method of using the difference insolubility. For example, an element having a two-layer structure of ahole injection layer formed from water-soluble polythiophene polystyrenesulfonate (PEDOT: PSS), and a light emitting layer formed by using anaromatic organic solvent such as toluene. In this case, since the PEDOT:PSS layer does not dissolve in an aromatic solvent such as toluene, itis possible to produce a two-layer structure.

However, when water-soluble PEDOT: PSS is used, the moisture remainingin the thin film needs to be removed, and this removal of moisture isdifficult and causes deterioration of the properties of the organicelectronic element. Further, for the removal of moisture, it isnecessary to dry the element at high temperature for a long time period,so that production of an organic electronic element on a resin substrateis difficult, or significant restrictions are imposed on the process,such as reduced pressure conditions.

Furthermore, there has been disclosed, as an example using an organicsolvent, a method of selecting a solvent that does not affect a lowerlayer that has been formed earlier (see Patent Document 1).

However, in such a method, the solvent that can be used is limited to asolvent that does not dissolve the lower layer, and therefore, there isa problem that only a narrow choice of materials is available. Further,a certain degree of erosion occurs in the lower layer at the time of theformation of an upper layer.

Furthermore, Non-Patent Document 1 suggests an element having athree-layer structure which uses compounds having largely differentsolubility.

Patent Document 2 also discloses an element having, on a PEDOT: PSSlayer, a three-layer structure into which a layer called interlayer hasbeen introduced.

In order to overcome such problems, Non-Patent Documents 2 to 4 andPatent Document 3 disclose methods of making a thin film insoluble to asolvent by utilizing a polymerization reaction of a siloxane compound,an oxetane group, a vinyl group or the like and thereby changing thesolubility of the compound.

Methods for providing a multilayer structure as such are important.However, there is the problem described above that is attributable tothe moisture remaining in the thin film when water-soluble PEDOT: PSS isused, or there are problems that there are restrictions on the materialthat can be used, in order to utilize the difference in solubility, thatsiloxane compounds are unstable to moisture in air, and that theproperties of the element are not satisfactory.

Further, in the case of utilizing a polymerization reaction, it isnecessary to add an appropriate polymerization initiator that generatesan acid, a base, a radical or the like, and to thereby initiate thepolymerization reaction through stimulation such as light or heat.

As a cause for initiating the polymerization reaction, heating or acombined use of light irradiation and heating is generally used, and inorder to bring the polymerization reaction to a sufficient extent, it isneeded to heat the reaction system at a temperature of 120° C. or higher(Non-Patent Document 4 and Non-Patent Document 5).

Here, there is a need to apply a substrate made of an inexpensive andflexible resin in the production of a flexible organic EL element inview of reducing the production cost for organic EL elements. However,since such a substrate undergoes softening, decomposition ordegeneration due to high temperature, there is a problem that the methodof bringing the polymerization reaction cannot be utilized.

In addition, a method of using a crosslinking reaction has beensuggested as another method of producing a multilayer structure. PatentDocument 4 discloses a method of crosslinking triphenylamine-containingether polyether ketone by ultraviolet irradiation, and thereby makingthe compound insoluble. In order to make the compound sufficientlyinsoluble through this method, there is a problem that ultravioletirradiation for a long time period is required, and decomposition oftriphenylamine or the like occurs.

Furthermore, Patent Document 5, Patent Document 6, Non-Patent Document6, and Non-Patent Document 7 disclose the production of a multilayerstructure through crosslinking of an oxetane group. In these methods,photoinitiators are used, and therefore, there is a concern fordeterioration due to light. Furthermore, there is a problem thatsufficient insolubilization at low temperature does not proceed, and,and the application of resin substrates which require low temperaturecuring is restricted, or there is a problem that at the time of formingan upper layer, the upper layer and the lower layer are intermixed,causing deterioration of the organic EL characteristics. Moreover, thephotoinitiators used in these methods are general iodonium salts orsulfonium salts, and there is a concern for the influence of thesecompounds on the EL characteristics.

On the other hand, an investigation is being conducted on the use of aniodonium salt or sulfonium salt having the same structure as that of thephotoinitiators in the hole transport layer or the light emitting layer,for the purpose of lowering the driving voltage, which is a problem fororganic EL elements.

Patent Document 7 discloses an ionic compound, but this has the samestructure as that of the photoinitiator described above, and thus thereis a concern for the influence of the compound on the properties of theorganic EL elements. Furthermore, there are no descriptions oncrosslinking or lamination.

Patent Document 8 discloses a polymer illuminant composition containinga polymer illuminant and an ion pair. There is a description that alight emitting element having a much longer lifetime may be obtained byincorporating an ion pair having a specific structure according to thedisclosure, but there are no descriptions on the injection and transportof charges. There are also no descriptions on crosslinking orlamination.

CITATION LIST Patent Documents

Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No.2003-07763

Patent Document 2: JP-A No. 2007-119763

Patent Document 3: WO 2008/010487

Patent Document 4: Japanese Patent No. 3643433

Patent Document 5: JP-A No. 2004-199935

Patent Document 6: Japanese Patent Application NationalPublication(Laid-Open) No. 2007-514298

Patent Document 7: WO 05/08924

Patent Document 8: JP-A No. 2005-179634

Non-Patent Documents

Non-Patent Document 1: Y. Goto, T. Hayashida, M. Noto, IDW '04Proceedings of the 11th International Display Workshop, 1343-1346 (2004)

Non-Patent Document 2: H. Yan, P. Lee, N. R., Armstrong, A. Graham, G A.Evemenko, P. Dutta, T. J. Marks, J. Am. Chem. Soc., 127, 3172-4183(2005)

Non-Patent Document 3: E. Bacher, M. Bayerl, P. Rudati, N. Reckfuss, C.David, K. Meerholz, O. Nuyken, Macromolecules, 38, 1640 (2005)

Non-Patent Document 4: M. S. Liu, Y. H. Niu, J. W. Ka, H. L. Yip, F.Huang, J. Luo, T. D. Wong, A. K. Y. Jen, Macromolecules, 41, 9570 (2008)

Non-Patent Document 5: B. Ma, F. Lauterwasser, L. Deng, C. S. Zonte, B.J. Kim, J. M. J. Frchet, C. Borek, M. E. Thompson, Chem. Mater., 19(19),4827 (2007)

Non-Patent Document 6: Macromol. Rapid Commun., 20, 224-228 (1999)

Non-Patent Document 7: Nature, 421 (2003) 829-833

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

In order to achieve an increase in the efficiency and an extension ofthe lifetime of an organic EL element, it is desirable to provide amultilayer structure for the organic layers and to separate thefunctions among the respective layers. However, in the case of producingan organic EL element by a coating method, in order to provide amultilayer structure for the organic layers using a wet process whichfacilitates film formation even in large-sized elements, it is necessaryto prevent the lower layer from dissolving when the upper layer isformed. Furthermore, there is a problem that when a film that isinsoluble in solvents is formed on a flexible substrate using apolymerization reaction, heating at higher temperature cannot beapplied.

In view of the problems described above, an object of the presentinvention is to provide an organic electronic material which can beeasily produced to have a multilayer structure and can also be used on asubstrate that cannot be treated at high temperature, such as a resin,and an ink composition containing the organic electronic material.Another object of the present invention is to provide an organic thinfilm which is formed by using the organic electronic material or the inkcomposition, an organic electronic element which uses the organic thinfilm and has superior light emission efficiency and a superior emissionlifetime than conventional electronic elements, an organic EL element, alighting device, and a display device which includes the organic ELelement and the lighting device.

Furthermore, another object of the present invention is to provide, inview of the problems described above, an organic electronic materialwith which an organic electronic element capable of lowering of thedriving voltage or stable long-term driving, can be produced. Stillanother object of the present invention is to provide an organicelectronic material that can be cured at low temperature by a coatingmethod, and a multilayer organic electronic element using the organicelectronic material. Still another object of the present invention is toprovide an organic electroluminescent element, a display element, and alighting device.

Means for Solving the Problem

The inventors of the present invention conductive a thoroughinvestigation, and as a result, they found that an organic electronicmaterial containing a polymer or oligomer which has a structurebranching in three or more directions and has at least one or morepolymerizable substituents, and an ink composition containing theorganic electronic material, can stably and easily form a thin film, andthat the solubility changes through a polymerization reaction. Theinventors also found that when an organic thin film formed by using theorganic electronic material or the ink composition is used in an organicelectronic element, particularly an organic EL element, a lightingdevice, and a display device including the elements, the organic thinfilm can lower the driving voltage and increase the light emissionefficiency. Thus, the inventors finally completed the present invention.

Furthermore, the inventors conducted a thorough investigation, and as aresult, they found that when an ionic compound having a particularcounter cation, which is not the iodonium or sulfonium used as a generalphotoinitiator, and a charge transporting compound are contained,lowering of the driving voltage or stable long-term driving can beachieved, thus completing the present invention.

That is, the present invention provides the following items.

(1) An organic electronic material containing a polymer or oligomerwhich has a structure branching in three or more directions and has atleast one polymerizable substituent.

(2) The organic electronic material as set forth in the item (1),wherein the polymer or oligomer contains at least any one of thestructures of the following formulas (1) to (10) as a unit serving asthe starting point for forming the branched structure.

(wherein Ar's each independently represent a divalent linking group,each representing an arylene group or heteroarylene group having 2 to 30carbon atoms; W represents a trivalent linking group, which is an atomicgroup obtained by further excluding one hydrogen atom from the arylenegroup or the heteroarylene group and may be substituted; Y's eachindependently represent a divalent linking group; and Z represents anyone of a carbon atom, a silicon atom and a phosphorus atom.)

(3) The organic electronic material as set forth in the item (2),wherein Y in the formula (4) or (7) is a divalent linking grouprepresented by one of the following formulas.

(wherein R's each independently represent a hydrogen atom, an optionallysubstituted, linear, cyclic or branched alkyl group having 1 to 22carbon atoms, or an optionally substituted aryl group or heteroarylgroup having 2 to 30 carbon atoms.)

(4) The organic electronic material as set forth in any one of the items(1) to (3), wherein the polymer or oligomer contains at least one chargetransporting group.

(5) The organic electronic material as set forth in any one of the items(1) to (4), wherein the polymer or oligomer contains at least onepolymerizable substituent.

(6) The organic electronic material as set forth in the item (5),wherein the polymerizable substituent is introduced into an end of thepolymer or oligomer.

(7) The organic electronic material as set forth in the item (5) or (6),wherein three or more of the polymerizable substituents are introducedinto one molecule of the polymer or oligomer.

(8) The organic electronic material as set forth in any one of the items(5) to (7), wherein the polymerizable substituent is any one of anoxetane group, an epoxy group, a vinyl group, an acrylate group and amethacrylate group.

(9) The organic electronic material as set forth in any one of the items(1) to (8), wherein the polymer or oligomer has a partial structurerepresented by one of the following formulas.

(wherein A₁ and A₂ each independently represent a trivalent linkinggroup; A₃ and A₄ each independently represent a tetravalent linkinggroup; L₁ to L₁₀ each independently represent a divalent linking group;X_(m) represents a divalent linking group; n represents an integer of 1or greater; and m represents 1 or an integer from 1 to n.)

(10) The organic electronic material as set forth in any one of theitems (1) to (9), wherein the number average molecular weight of thepolymer or oligomer is from 1,000 to 1,000,000.

(11) The organic electronic material as set forth in any one of theitems (1) to (10), wherein the polydispersity of the polymer or oligomeris greater than 1.0.

(12) The organic electronic material as set forth in any one of theitems (1) to (11), further containing a dopant.

(13) The organic electronic material as set forth in any one of theitems (1) to (12), further containing a polymerization initiator.

(14) The organic electronic material as set forth in the item (13),wherein the polymerization initiator is a thermal polymerizationinitiator.

(15) The organic electronic material as set forth in the item (13),wherein the polymerization initiator is an ionic compound.

(16) The organic electronic material as set forth in the item (14) or(15), wherein the polymerization initiator also functions as a dopant.

(17) An ink composition including the organic electronic material as setforth in any one of the items (1) to (16).

(18) An organic thin film produced using the organic electronic materialas set forth in any one of the items (1) to (16) or the ink compositionas set forth in the items (17).

(19) An organic electronic element including the organic thin film asset forth in the item (18).

(20) An organic electroluminescent element including the organic thinfilm as set forth in the item (18).

(21) An organic electroluminescent element formed by laminating at leasta substrate, an anode, a hole injection layer, a light emitting layerand a cathode, wherein the hole injection layer is a layer formed fromthe organic thin film as set forth in the item (18).

(22) An organic electroluminescent element formed by laminating at leasta substrate, an anode, a hole transport layer, a light emitting layerand a cathode, wherein the hole transport layer is a layer formed fromthe organic thin film as set forth in the item (18).

(23) An organic electroluminescent element formed by laminating at leasta substrate, an anode, a light emitting layer and a cathode, wherein thelight emitting layer is a layer formed from the organic thin film as setforth in the item (18).

(24) The organic electroluminescent element as set forth in any one ofthe items (20) to (23), wherein the emission color is white.

(25) The organic electroluminescent element as set forth in any one ofthe items (20) to (24), wherein the substrate is a flexible substrate.

(26) The organic electroluminescent element as set forth in any one ofthe items (20) to (25), wherein the substrate is a resin film.

(27) A display element including the organic electroluminescent elementas set forth in any one of the items (20) to (26).

(28) A lighting device including the organic electroluminescent elementas set forth in any one of the items (20) to (26).

(29) A display device including the lighting device as set forth in theitem (28), and a liquid crystal element as a display unit.

(30) An organic electronic material containing at least an ioniccompound and a compound having a charge transporting unit (hereinafter,referred to as a charge transporting compound), wherein the ioniccompound is composed of a counter cation and a counter anion, and thecounter cation is any one kind or two or more kinds of H⁺, acarbocation, a nitrogen cation, an oxygen cation, and a cation having atransition metal.

(31) The organic electronic material as set forth in the item (30),wherein the carbocation is a tertiary carbocation.

(32) The organic electronic material as set forth in the item (30) or(31), wherein the nitrogen cation is a tertiary or quaternary nitrogencation.

(33) The organic electronic material as set forth in any one of theitems (30) to (32), wherein the counter anion is any one kind or two ormore kinds of fluorophosphates ions, fluorinated alkyl fluorophosphateions, borate ions, and fluoroantimonate ions.

(34) The organic electronic material as set forth in any one of theitems (30) to (33), wherein the charge transporting compound has atleast one structure selected from triarylamine, carbazole, andthiophene.

(35) The organic electronic material as set forth in any one of theitems (30) to (33), wherein the charge transporting compound is apolymer or oligomer containing a repeating unit represented by any oneof the following formulas (1a) to (7a) and having hole transportproperties.

(wherein Ar₁ to Ar₂₀ each independently represent an aryl group orheteroaryl group having 2 to 30 carbon atoms, or a substituted orunsubstituted arylene group or heteroarylene group. Here, the aryl grouprepresents an atomic group obtained by excluding one hydrogen atom froman aromatic hydrocarbon, and a heteroaryl group represents an atomicgroup obtained by excluding one hydrogen atom from an aromatic compoundhaving a heteroatom; R's each independently represent —R¹, —OR², —SR³,—OCOR⁴, —COOR⁵, —SiR⁶R⁷R⁸, or one of the formulas (2a) to (4a) (providedthat R′ to R⁸ each represent a hydrogen atom, a linear, cyclic orbranched alkyl group having 1 to 22 carbon atoms, or an aryl group orheteroaryl group having 2 to 30 carbon atoms). Here, the arylene grouprepresents an atomic group obtained by excluding two hydrogen atoms froman aromatic hydrocarbon, and a heteroarylene group represents an atomicgroup obtained by excluding two hydrogen atoms from an aromatic compoundhaving a heteroatom. X represents a group obtained by further removingone hydrogen atom from a group having one or more hydrogen atomsselected among the groups represented by R.

(36) The organic electronic material as set forth in any one of theitems (30) to (35), wherein the charge transporting compound has one ormore polymerizable substituents.

(37) The organic electronic material as set forth in the item (36),wherein the polymerizable substituent is any one or oxetane, epoxy andvinyl ether.

(38) The organic electronic material as set forth in any one of theitems (30) to (37), further containing a solvent.

(39) The organic electronic material as set forth in any one of theitems (30) to (38), wherein the ionic compound is an electron-acceptingcompound, and the charge transporting compound can be one-electronoxidized by the ionic compound.

(40) An organic electronic element having a layer formed by applying theorganic electronic material as set forth in any one of the items (30) to(39) on a substrate.

(41) The organic electronic element as set forth in the items (40),wherein the layer thus formed is insolubilized.

(42) The organic electronic element as set forth in the item (41),wherein another layer is further formed on the insolubilized layer toobtain a multilayer structure.

(43) The organic electronic element as set forth in any one of the items(40) to (42), wherein the substrate is a resin film.

(44) An organic electroluminescent element having a layer formed fromthe organic electronic material as set forth in any one of the items(30) to (39).

(45) An organic electroluminescent element formed by laminating at leasta substrate, an anode, a hole injection layer, a polymerized layer, alight emitting layer and a cathode, wherein the polymerized layer is alayer formed from the organic electronic material as set forth in anyone of the items (40) to (39).

(46) An organic electroluminescent element formed by laminating at leasta substrate, an anode, a polymerized layer, a hole transport layer, alight emitting layer and a cathode, wherein the polymerized layer is alayer formed from the organic electronic material as set forth in anyone of the items (30) to (39).

(47) The organic electroluminescent element as set forth in any one ofthe items (40) to (46), wherein the emission color is white.

(48) The organic electroluminescent element as set forth in any one ofthe items (45) to (47), wherein the substrate is a flexible substrate.

(49) The organic electroluminescent element as set forth in any one ofthe items (45) to (47), wherein the substrate is a resin film.

(50) A display element including the organic electroluminescent elementas set forth in any one of the items (44) to (49).

(51) A lighting device including the organic electroluminescent elementas set forth in any one of the items (44) to (49).

(52) A display device including the lighting device as set forth in theitem (51), and a liquid crystal element as a display unit.

(53) The organic electronic material as set forth in any one of theitems (1) to (16), further containing an ionic compound composed of acounter cation and a counter anion, wherein the counter cation is anyone kind or two or more kinds of H⁺, a carbocation, a nitrogen cation,an oxygen cation, and a cation having a transition metal.

The present patent application claims priority based on Japanese PatentApplication previously filed by the same Applicant, that is, No.2009-131931 (filed on Jun. 1, 2009), the disclosure of which has beenincorporated herein by reference.

Effect of the Invention

According to the present invention, since a thin film can be stably andeasily formed, and the solubility changes through a polymerizationreaction, construction of a multilayer structure of organic thin filmlayers can be easily achieved. Furthermore, since a sufficient change inthe solubility can be obtained at low temperature, an organic electronicmaterial that can be applied to a flexible substrate such as a resinsubstrate, and an ink composition containing the organic electronicmaterial can be provided. Further, according to the present invention,an organic thin film which is formed by using the organic electronicmaterial or the ink composition, an organic electronic element whichuses the organic thin film and has superior light emission efficiencyand a superior emission lifetime than conventional electronic elements,an organic EL element, a lighting device, and a display device whichincludes the organic EL element and the lighting device.

Further, according to the present invention, an organic electronicmaterial which can produce an organic electronic element capable oflowering of the driving voltage or stable long-term driving, and can becured at low temperature by a coating method, a multilayered organicelectronic element using the organic electronic material, an organicelectroluminescent element, a display element and a lighting device canbe provided. An organic electronic element, particularly an organic ELelement, which is capable of lowering of the driving voltage or stablelong-term driving can be provided by incorporating an ionic compound anda charge transporting compound.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing an example of a multilayeredorganic EL element.

BEST MODES FOR CARRYING OUT THE INVENTION

According to a first aspect, an organic electronic material of thepresent invention is characterized by containing a polymer or oligomerwhich has a structure branching in three or more directions and has atleast one polymerizable substituent.

The term “structure branching in three or more directions” according tothe present invention is a structure in which the main chain of thepolymer or oligomer is not in a linear form but has branches at anysite. Now, the details of the structure will be described below.

[Structure Branching in Three or More Directions]

The polymer or oligomer according to the present invention has astructure branching in three or more directions, from the viewpoint oflowering the temperature for carrying out a sufficient polymerizationreaction. Furthermore, this branched structure can elevate the glasstransition temperature of the polymer or oligomer, and therebycontributes to an enhancement of the heat resistance of the polymer oroligomer.

This branched structure refers to the state in which when a chain havingthe highest degree of polymerization among the various chains in onemolecule of the polymer or oligomer is designated as the main chain,side chains having an equal degree of polymerization or a lower degreeof polymerization are linked to the main chain. The degree ofpolymerization according to the present invention indicates how manymonomer units that are used to synthesize the polymer or oligomer, areincluded in one molecule of the polymer or oligomer. The side chain asused in the present invention means a chain that is different from themain chain of the polymer or oligomer, and has at least one or morepolymerized units. Any moiety other than that is considered not as aside chain but as a substituent.

As the method for forming a branched structure, a polymer or oligomermay be formed by using a monomer having three or more polymerizablesites in one molecule, or a branched structure may also be formed byforming a linear-shaped polymer or oligomer, and then polymerizing thoselinear-shaped chains. Thus, there are no particular limitations.

Specifically, the polymer or oligomer preferably contains any one of thestructures of the following formulas (1) to (10) as the unit serving asa starting point for forming a branched structure in the polymer oroligomer.

(wherein Ar's each independently represent a divalent linking group, andeach represents an arylene group or heteroarylene group having 2 to 30carbon atoms. The arylene group is an atomic group obtained by excludingtwo hydrogen atoms from an aromatic hydrocarbon, and may be substituted.Examples thereof include phenylene, biphenyldiyl, terphenyldiyl,naphthalenediyl, anthracenediyl, tetracenediyl, fluorenediyl, andphenanthrenediyl. The heteroaryl group is an atomic group obtained byexcluding two hydrogen atoms from an aromatic compound having aheteroatom, and may be substituted. Examples thereof includepyridinedyl, pyrazinediyl, quinolinediyl, isoquinolinediyl,acridinediyl, phenanthrolinediyl, furanediyl, pyrrolediyl,thiophenediyl, oxazolediyl, oxadiazolediyl, thiadiazolediyl,triazolediyl, benzoxazolediyl, benzoxadiazolediyl, benzothiadiazolediyl,benzotriazolediyl, and benzothiophenediyl. W represents a trivalentlinking group, and is an atomic group obtained by further excluding onehydrogen atom from the arylene group or heteroarylene group, and may besubstituted. Y's each independently represent a divalent linking group.Z represents any one of a carbon atom, a silicon atom and a phosphorusatom.)

Y in the formulas (1) and (7) is preferably a divalent linking grouprepresented by one of the following formulas.

(wherein R's each independently represent a hydrogen atom, a linear,cyclic or branched alkyl group having 1 to 22 carbon atoms, or an arylgroup or heteroaryl group having 2 to 30 carbon atoms. Here, the arylgroup is an atomic group obtained by excluding one hydrogen atom from anaromatic hydrocarbon, and may be substituted. The heteroaryl group is anatomic group obtained by excluding one hydrogen atom from an aromaticcompound having a heteroatom, and may be substituted.)

[Charge Transporting Group]

Furthermore, the polymer or oligomer according to the present inventionpreferably contains at least one “charge transporting group” in order toexhibit the transport capability for holes or electrons. Here, the“charge transporting group” is a substituent which makes the polymer oroligomer to have a function of transporting holes or electrons, and thedetails thereof will be described below.

The charge transporting group may be any group having an ability totransport holes or electrons, and particularly preferred examplesinclude, but are not limited to, an amine or a carbazole having anaromatic ring, thiophene, fluorene, phenylene, biphenylene,terphenylene, naphthalene, anthracene, tetracene, phenanthrene,pyridine, pyrazine, quinoline, isoquinoline, acridine, furan, pyrrole,oxazole, oxadiazole, thiadiazole, triazole, benzoxazole, benzoxadiazole,benzothiadiazole, benzotriazole, and benzothiophene. Particularly, fromthe viewpoint of the transport of holes, a structure containing anaromatic amine, carbazole, thiophene, fluorene, phenylene or pyrrolemoiety is preferred, and from the viewpoint of the transport ofelectrons, a structure containing a fluorene, phenylene, phenanthrene,pyridine or quinoline moiety is preferred. For example, chargetransporting groups having partial structures represented by thefollowing formulas are preferred.

(wherein in the above formulas, R's each independently represent ahydrogen atom, a halogen atom, a linear, cyclic or branched alkyl grouphaving 1 to 22 carbon atoms, an alkenyl group, an alkynyl group, analkoxy group, or an aryl group or heteroaryl group having 2 to 30 carbonatoms. Here, the aryl group is an atomic group obtained by excluding onehydrogen atom from an aromatic hydrocarbon, and may be substituted. Theheteroaryl group is an atomic group obtained by excluding one hydrogenatom from an aromatic compound having a heteroatom, and may besubstituted. Furthermore, adjacent R's may also be joined to form aring. Ar's each independently represent an arylene group orheteroarylene group having 2 to 30 carbon atoms. The arylene group is anatomic group obtained by excluding two hydrogen atoms from an aromatichydrocarbon, and may be substituted. Examples thereof include phenylene,biphenyldiyl, terphenyldiyl, naphthalenediyl, anthracenediyl,tetracenediyl, fluorenediyl, and phenanthrenediyl. The heteroaryl groupis an atomic group obtained by excluding two hydrogen atoms from anaromatic compound having heteroatoms, and may be substituted. Examplesthereof include pyridinediyl, pyrazinediyl, quinolinediyl,isoquinolinediyl, acridinediyl, phenanthrolinediyl, furanediyl,pyrrolediyl, thiophenediyl, oxazolediyl, oxadiazolediyl,thiadiazolediyl, triazolediyl, benzoxazolediyl, benzoxadiazolediyl,benzothiadiazolediyl, benzotriazolediyl, and benzothiophenediyl.)

[Polymerizable Substituent]

Furthermore, the polymer or oligomer according to the present inventionpreferably has at least one “polymerizable substituent”, from theviewpoint of curing the polymer or oligomer through a polymerizationreaction and thereby changing the solubility in a solvent. Here, theterm “polymerizable substituent” is a substituent capable of forming anintermolecular bond between two or more molecules through apolymerization reaction, and the details thereof will be describedbelow.

Examples of the polymerizable substituent include a group having acarbon-carbon multiple bond (examples include a vinyl group, anacetylene group, a butenyl group, an acryl group, an acrylate group, anacrylamide group, a methacryl group, a methacrylate group, amethacrylamide group, an arene group, an allyl group, a vinyl ethergroup, a vinylamino group, a furyl group, a pyrrole group, a thiophenegroup, and a silol group), a group having a small ring (examples includea cyclopropyl group, a cyclobutyl group, an epoxy group, an oxetanegroup, a diketene group, and an episulfide group), a lactone group, alactam group, and a group containing a siloxane derivative. Furthermore,in addition to the groups described above, a combination of groupscapable of forming an ester bond or an amide bond can also be utilized.Examples include a combination of an ester group and an amino group, anda combination of an ester group and a hydroxyl group. Particularly, aspolymerizable substituent, an oxetane group, an epoxy group, a vinylgroup, an acrylate group and a methacrylate group are preferred, andfrom the viewpoints of reactivity and the properties of organicelectronic elements, an oxetane group and an epoxy group are morepreferred. Examples include groups represented by the followingformulas. From the viewpoint of increasing the degree of freedom of thepolymerizable substituent and thereby making it easier to bring a curingreaction, it is more preferable that the main chain of the polymer oroligomer and the polymerizable substituent be linked via an alkyl chainhaving 1 to 8 carbon atoms. Furthermore, from the viewpoint ofincreasing the affinity with a hydrophilic electrode such as ITO, thealkyl chain is more preferably a hydrophilic group such as ethyleneglycol or diethylene glycol. Further, from the viewpoint making theregulation of the corresponding monomer easier, the polymerizablesubstituent may also have an ether bond at the end of the alkyl chain,that is, the linkage to the polymerizable substituent, or in the linkageto the polymer or oligomer main chain.

The polymerizable substituent may be introduced into the main chain ofthe polymer or oligomer branching in three or more directions, may beintroduced into a side chain, or may be introduced into both the mainchain and a side chain. Furthermore, when the polymerizable substituentis introduced into the main chain and/or the end of a side chain only,it is particularly preferable because the number of the chargetransporting group increases relative to the number of the polymerizablesubstituent, and the charge transport properties can be enhanced.Furthermore, it is preferable that three or more of the polymerizablesubstituents be introduced into one molecule of the polymer or oligomer,from the viewpoint that an insolubilized film can be produced bysufficiently changing the solubility even at a temperature around 100°C. The polymerizable substituent is such that as the number of thesubstituents is larger, the polymerizable substituents contribute moreto low temperature curing. However, if the number is too large, thepolymerizable substituents have an adverse effect on the hole transportproperties, and therefore, it is preferable that the polymerizablesubstituent be introduced while taking this into consideration.

As a method for introducing a polymerizable substituent into the polymeror oligomer, there are no particular limitations, and the polymerizablesubstituent may be introduced by incorporating a monomer having apolymerizable substituent into the synthesis system and copolymerizingthe monomer with a monomer that forms the main chain, or may also beintroduced by forming the main chain of the polymer or oligomer and thenfurther allowing the main chain to react with a monomer having apolymerizable substituent. From the viewpoint of convenientlysynthesizing the polymer or oligomer having a polymerizable substituent,a method of incorporating a monomer having a polymerizable substituentinto the synthesis system is more preferred.

Furthermore, in order to obtain a sufficient change in solubility afterthe polymerization reaction, it is preferable that the polymer oroligomer have three or more polymerizable substituents in one molecule.The number of polymerizable substituents in one molecule of the polymeror oligomer can be estimated based on the molecular weight of thepolymer or oligomer, and the ratio of the integrated value of thesignals originating from an oxetane group, an epoxy group, a vinylgroup, an acrylate group, a methacrylate group or the like in the ¹H-NMRspectrum of the polymer or oligomer with respect to the sum ofintegrated values. If the number of the polymerizable substituents issmaller than this, a sufficient change in the solubility is notobtained, and therefore, there is a risk that the polymer or oligomermay be re-dissolved in the solvent, making the lamination processdifficult.

Furthermore, it is preferable that the polymer or oligomer according tothe present invention contain a partial structure represented by one ofthe following formulas, from the viewpoint that the polymer chains orthe oligomer chains are entangled with each other, so that a change inthe solubility is easily achieved, and the glass transition temperatureof the polymer or oligomer is increased, causing an enhancement of theheat resistance.

(wherein A₁ and A₂ each independently represent a trivalent linkinggroup; A₃ and A₄ each independently represent a tetravalent linkinggroup; L₁ to L₁₀ each independently represent a divalent linking group;X_(m) represents a divalent linking group; n represents an integer of 1or greater; and m represents 1 or an integer from 1 to n.)

As the trivalent linking group represented by A₁ and A₂, the formulas(1), (2), (5) and (6) exemplified for the branched structure containedin the polymer or oligomer previously described are preferred, and asthe tetravalent linking group represented by A₃ and A₄, the sameformulas (3), (4), (7), (8), (9) and (10) are preferred.

Furthermore, as the divalent linking group represented by L₁ to L₁₀ orX_(m), the divalent groups exemplified in the description on Y in theformulas (4) or (7) previously described, or the divalent groupsexemplified in the description on the electron transporting group, arepreferred.

[Method for Producing Polymer or Oligomer]

The polymer or oligomer used in the present invention can be produced byvarious synthesis methods that are known to those having ordinary skillin the art. For example, in the case of producing the polymer oroligomer by coupling a monomer having an aromatic ring to anothermonomer having an aromatic ring, the methods described in T. Yamamoto,et al., Bull. Chem. Soc. Jap., Vol. 51, No. 7, p. 2091 (1978) and M.Zembayashi, et al., Tetrahedron Lett., Vol. 47, p. 4089 (1977); themethod reported by A. Suzuki in Synthetic Communications, Vol. 11, No.7, p. 513 (1981); the method described in S. L. Buchwald and J. F.Hartwig, et al., Tetrahedron Lett., Vol. 21, p. 3609 (1995); and themethod described in T. Migita, M. Kosugi, and J. K. Stille, et al.,Angew. Chem. Int. Ed. Engl., No. 25, p. 508 (1986) can be used, butthere are no particular limitations. The reaction by Suzuki andcolleagues induces a Pd catalysed cross-coupling reaction between anaromatic boronic acid derivative and an aromatic halide (usuallyreferred to as “Suzuki Reaction”), and this reaction is preferable fromthe viewpoint that the polymer or oligomer used in the present inventioncan be conveniently produced by utilizing the reaction of bondingbetween corresponding aromatic rings.

In the Suzuki Reaction, a Pd(0) or Pd(II) compound is mainly used as acatalyst, but in recent years, a Ni compound has also been used in somecases. Thus, use can be made of any of the catalysts. When a Pd compoundis used, a Pd compound having a phosphine ligand, such as Pd(PPh₃)₄(tetrakis(triphenylphosphine)palladium(0)), Pd(dppf)Cl₂([1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloride), andPd(dppe)Cl₂ ([1,2-bis(diphenylphosphino)ethane]palladium(II)dichloride), can be directly used, or a catalyst species can begenerated by using tris(dibenzylideneacetone)dipalladium(0),palladium(II) acetate or the like as a precursor, and mixing theprecursor with a phosphine ligand in the system. In this case, a knowncommercially available phosphine compound such as P(t-Bu)₃(tris(t-butyl)phosphine), tributylphosphine or P(c-hex)₃(tricyclohexylphosphine) can be used as the phosphine ligand. In regardto the concentration of the catalyst species, the reaction can becarried out at any concentration in the range of about 0.01% to 5% bymole based on the monomer to react. As the reaction solvent, a mixedsolvent system of water and an organic solvent is mainly used, and asthe organic solvent, dimethoxyethane, toluene, anisole, tetrahydrofuran,acetone, acetonitrile, N,N-dimethylformamide or the like can be used.Furthermore, as a base, a carbonate of an alkali metal, such as Na₂CO₃or K₂CO₃; a hydroxide of an alkali metal, such as NaOH or KOH;triethylamine, K₃PO₄, or a water-soluble organic base such as TMAH(tetramethylammonium hydroxide) or TEAH (tetraethylammonium hydroxide)can be used. Furthermore, the reaction can be accelerated by adding aphase transfer catalyst, and representative examples of the phasetransfer catalyst include TBAB (tetrabutylammonium bromide) and Aliquat(registered trademark) 336 (manufactured by Sigma Aldrich Company, amixture of trioctylmethylammonium chloride and tricaprylylmethylammoniumchloride).

Examples of the instance of producing the polymer or oligomer used inthe present invention by the Suzuki reaction will be described in thefollowing items <1> to <3>, but the synthesis method for the polymer oroligomer according to the present invention is not intended to belimited to these.

<1> Coupling between a monomer (I) which serves as a starting point forforming a structure branching in three directions, a monomer (II) whichis capable of coupling with the monomer (I), and a monomer (III) whichcontains a polymerizable substituent and is capable of coupling with themonomer (II)

<2> Coupling of a monomer (IV) which serves as a starting point forforming a structure branching in three directions, a monomer (V) whichis capable of coupling with the monomer (IV), a monomer (VI) which iscapable of coupling with the monomer (V), and a monomer (VII) which hasa polymerizable substituent and is capable of coupling with the monomer(V)

<3> Coupling of a monomer (VIII) which serves as a starting point forforming a structure branching in four directions, a monomer (IX) whichis capable of coupling with the monomer (VIII), and a monomer which hasa polymerizable substituent and is capable of coupling with the monomer(IX)

Furthermore, as examples of the structure of the polymer or oligomeraccording to the present invention, structural examples of the compoundsobtained by the syntheses of the above items <1> to <3> will be shown inthe following items <4> to <6>. The following formulas are only forillustrative purposes, and are not intended to represent the number ofrepeating units. Further, although polymerizable substituents are to beintroduced into the structures, hydrogen atoms or halogen atoms may alsobe partially bonded to the structures.

<4> Structural example of the compound obtained by the coupling reactionof the item <1>

<5> Structural example of the compound obtained by the coupling reactionof the item <2>

<6> Structural example of the compound obtained by the coupling reactionof the item <3>

[Molecular Weight and Degree of Polymerization]

Furthermore, the number average molecular weight of the polymer oroligomer according to the present invention is preferably from 1,000 to1,000,000, and more preferably from 2,000 to 800,000. Even morepreferably, the number average molecular weight is from 3,000 to600,000. If the molecular weight is less than 1,000, there is a tendencythat the polymer or oligomer undergoes crystallization easily, and thefilm-forming stability decreases. If the molecular weight is larger than1,000,000, there is a tendency that the solubility in solventsdecreases, the coating workability is deteriorated, and preparation ofan ink composition becomes difficult. Here, the number average molecularweight of the polymer or oligomer is a number average molecular weightwhich is measured by gel permeation chromatography and calculatedrelative to polystyrene standards.

The degree of polymerization of the polymer or oligomer used in thepresent invention is preferably from 5 to 1,000, and more preferablyfrom 10 to 500. If the value of n is too small, the film-formingstability tends to decrease, and if the value is too large, thesolubility tends to decrease.

The polydispersity of the polymer or oligomer according to the presentinvention is preferably higher than 1.0, and from the viewpoint ofsuppressing fluctuations in the properties of organic electronicelements, the polydispersity is more preferably from 1.1 to 5.0, andmost preferably from 1.2 to 3.0. On the other hand, from the viewpointof conveniently synthesizing the polymer or oligomer without regulatingthe molecular weight distribution, the polydispersity is more preferablyfrom 1.1 to 20.0, and most preferably from 1.2 to 15.0. If thepolydispersity is too low, the polymer or oligomer tends to become proneto aggregate after film formation, and if the polydispersity is toohigh, the properties of organic electronic elements tend to deteriorate.Here, the polydispersity of the polymer or oligomer is the ratio (weightaverage molecular weight/number average molecular weight) which ismeasured using gel permeation chromatography and calculated relative topolystyrene standards.

[Polymerization Initiator]

The organic electronic material of the present invention preferablyfurther contains a polymerization initiator, in addition to the polymeror oligomer, so as to polymerize the polymerizable substituent. Thispolymerization initiator may be any compound capable of exhibiting anability to polymerize the polymerizable substituent by applying heat,light, microwaves, radiation, or an electron beam, and using these incombination, and there are no particular limitations. However, thepolymerization initiator is more preferably a compound capable ofinitiating polymerization by means of radiation irradiation, lightirradiation or heating, and a compound capable of initiatingpolymerization by light irradiation (hereinafter, described as aphotoinitiator), or a compound capable of initiating polymerization byheating (hereinafter, described as a thermal initiator), from theviewpoint that polymerization can be initiated more conveniently. Thephotoinitiator may be any compound which exhibits an ability topolymerize the polymerizable substituent by irradiation with lighthaving a wavelength of 200 nm to 800, while the thermal initiator may beany compound which exhibits the same ability by heating at 300° C. orbelow, and there are no particular limitations. However, for example,when the polymerizable substituent is an oxetane group, an ioniccompound composed of a counter cation and a counter anion is preferredfrom the viewpoint of reactivity, and the details thereof will bdescribed below.

[Counter Cation]

Examples of the counter cation include H⁺, a carbenium ion, an ammoniumion, an anilinium ion, a pyridinium ion, an imidazolium ion, apyrrolidinium ion, a quinolinium ion, an immonium ion, an aminium ion,an oxonium ion, a pyrylium ion, a chromenylium, a xanthylium ion, aniodonium ion, a sulfonium ion, a phosphonium ion, a tropylium ion, and acation having a transition metal. From the viewpoint of reactivity, H⁺,a carbenium ion, an anilinium ion, an aminium ion, an iodonium ion, asulfonium ion, a phosphonium ion, and a tropylium ion are preferred.

[Counter Anion]

The counter anion may be any conventionally known anion, and examplesinclude halogen ions such as F⁻, Cl⁻, Br⁻ and I⁻; OH⁻; ClO₄ ⁻; sulfonateions such as FSO₃ ⁻, ClSO₃ ⁻, CH₃SO₃ ⁻, C₆H₅SO₃ ⁻, and CF₃SO₃ ⁻; sulfateions such as HSO₄ ⁻ and SO₄ ²⁻; carbonate ions such as HCO₃ ⁻ and CO₃²⁻; phosphate ions such as H₂PO₄ ⁻, HPO₄ ²⁻, and PO₄ ³⁻; fluorophosphateions such as PF₆ ⁻ and PF₅OH⁻; fluorinated alkyl fluorophosphate ionssuch as [(CF₃CF₂)₃PF₃]⁻, [(CF₃CF₂CF₂)₃PF₃]⁻, [((CF₃)₂CF)₃PF₃]⁻,[((CF₃)₂CF)₂PF₄]⁻, [((CF₃)₂CFCF₂)₃PF₃]⁻ and [((CF₃)₂CFCF₂)₂PF₄]⁻;fluoroalkanesulfonyl methide, imide ions such as (CF₃SO₂)₃C⁻ and(CF₃SO₂)₂N⁻; borate ions such as BF₄ ⁻, B(C₆F₅)₄ ⁻, and B(C₆H₄CF₃)₄ ⁻;fluoroantimonate ions such as SbF₆ ⁻ and SbF₅OH⁻; fluoroarsenate ionssuch as AsF₆ ⁻ and AsF₅OH⁻; AlCl₄ ⁻; and BiF₆. However, from theviewpoints of lowering the driving voltage of the organic electronicelement, and forming a polymerization initiator that allows lowtemperature curing when combined with the cations described above,fluorophosphate ions such as PF₆ ⁻ and PF₅OH⁻; fluorinated alkylfluorophosphate ions such as [(CF₃CF₂)₃PF₃]⁻, [(CF₃CF₂CF₂)₃PF₃]⁻,[((CF₃)₂CF)₃PF₃]⁻, [((CF₃)₂CF)₂PF₄]⁻, [((CF₃)₂CFCF₂)₃PF₃]⁻ and[((CF₃)₂CFCF₂)₂PF₄]⁻; fluoroalkanesulfonyl methide, imide ions such as(CF₃SO₂)₃C⁻ and (CF₃SO₂)₂N⁻; borate ions such as BF₄, B(C₆F₅)₄ ⁻ andB(C₆H₄CF₃)₄ ⁻; and fluoroantimonate ions such as SbF₆ and SbF₅OH⁻ arepreferred.

For the counter cations and counter anions, those exemplified inconnection with the ionic compound according to a second aspect of thepresent invention that will be described later, may also be used inaddition to the ions described above.

When the initiator is a photoinitiator, the photoinitiator may be usedin combination with a photosensitizer in order to enhancephotosensitivity. Examples of the photosensitizer include anthracenederivatives and thioxanthone derivatives.

The mixing ratio of the polymerization initiator is preferably in therange of from 0.1% by weight to 30% by weight, more preferably in therange of from 0.2% by weight to 25% by weight, and particularlypreferably in the range of from 0.5% to 20% by weight, relative to thetotal weight of the organic electronic material. If the mixing ratio ofthe polymerization initiator is less than 0.1% by weight, there is atendency that lamination is not easily achieved because the change inthe solubility is not sufficient. If the mixing ratio is greater than30% by weight, the properties of the electronic elements tend todeteriorate due to the polymerization initiator remaining in the thinfilm and/or the decomposition products.

The organic electronic material of the present invention preferablycontains a dopant so as to enhance the charge transport properties, andthe details thereof will be described below.

[Dopant]

The dopant according to the present invention may be any compound whichis capable of exhibiting a doping effect when added to the polymer oroligomer of the present invention, and thereby enhancing the chargetransport properties, and there are no particular limitations. Thedoping effect may be classified into the p-type doping in which thedopant works as an electron acceptor, and the n-type doping in which thedopant works as an electron donor. However, the dopant according to thepresent invention may be a dopant which exhibits any of the p-typedoping and the n-type doping. It is preferable to implement the p-typedoping for an enhancement of the hole transport properties, and toimplement the n-type doping for an enhancement of the electron transportproperties. Further, there are no limitations on the number of thedopant species, and plural dopants may be mixed and added.

The dopant used in the p-type doping may be an electron-acceptingcompound, and specific examples thereof include a Lewis acid, a protonicacid, a transition metal compound, an ionic compound, and a halogencompound. Examples include, as the Lewis acid, FeCl₃, PF₅, AsF₅, SbF₅,BF₅, BCl₃ and BBr₃; as the protonic acid, inorganic acids such as HF,HCl, HBr, HNO₅, H₂SO₄ and HClO₄, and organic acids such asbenzenesulfonic acid, p-toluenesulfonic acid, dodecylbenzenesulfonicacid, polyvinylsulfonic acid, methanesulfonic acid,trifluoromethanesulfonic acid, trifluoroacetic acid, 1-butanesulfonicacid, vinylphenylsulfonic acid, and camphor sulfonic acid; as thetransition metal compound, FeOCl, TiCl₄, ZrCl₄, HfCl₄, NbF₅, AlCl₃,NbCl₅, TaCl₅ and MoF₅; as the ionic compound, known perfluoro anionssuch as tetrakis(pentafluorophenyl)borate ion,tris(trifluoromethanesulfonyl)methide ion,bis(trifluoromethanesulfonyl)imide ion, hexafluoroantimonate ion, AsF₆ ⁻(hexafluoroarsenate ion), BF₄ ⁻ (tetrafluoroborate ion), and PF₆ ⁻(hexafluorophosphate ion), and ionic compounds having conjugated baseanions of the inorganic acids and organic acids mentioned above; and asthe halogen compound, Cl₂, Br₂, I₂, ICl, ICl₃, IBr, and IF. Furthermore,other electron-accepting compounds described in Japanese Patent Nos.4058842, 4186758 and 3996036, such as TCNE (tetracyanoethylene) and TCNQ(tetracyanoquinodimethane), can also be used. Preferred examples areLewis acids, ionic compounds, and other electron-accepting compoundssuch as TCNE and TCNQ.

As the dopant used in the n-type doping, alkali metals such as Li andCs; alkaline earth metals such as Mg; salts of alkali metals/alkalineearth metals such as LiF and Cs₂CO₃; various metal complexes; and otherelectron-donating organic compounds can be used.

Further, according to the present invention, it is preferable that thepolymerization initiator and the dopant be the same compound, from theviewpoint that the organic electronic material can be convenientlyproduced.

[Additives]

The organic electronic material of the present invention can be used, byitself, as a functional material for organic electronic elements.Further, the organic electronic material of the present invention can beused, by itself, as the hole injection layer, the hole transport layer,the electron blocking layer, the light emitting layer, the hole blockinglayer, the electron transport layer, or the electron injection layer oforganic EL elements. Moreover, the organic electronic material can stillbe used in organic electronic elements or organic EL elements, even ifvarious additives have been incorporated into the organic electronicmaterial. Examples of the additives include, if the organic electronicmaterial is used in the light emitting layer of an organic EL element,the polymerization initiator and the dopant described above, as well asa metal complex containing a central metal such as Jr or Pt, and anemitting dye; and if the organic electronic material is used in the holeinjection layer, hole transport layer, electron blocking layer, electrontransport layer or electron injection layer, the dopant, as well as anoxidizing agent, a reducing agent, an oxidation inhibitor, a reductioninhibitor, and a stabilizer.

[Ink Composition]

The ink composition of the present invention is characterized bycontaining the organic electronic material of the present inventiondescribed above. The details of the ink composition will be describedbelow. The ink composition of the present invention may contain theorganic electronic material and a solvent that can dissolve or dispersethe material, and may further contain other additives, for example, apolymerization inhibitor, a stabilizer, a thickening agent, a gellingagent, a flame retardant, an oxidation inhibitor, a reduction inhibitor,an oxidizing agent, a reducing agent, a surface modifier, an emulsifier,a defoamant, a dispersant, and a surfactant. Examples of the solventinclude water; alcohols such as methanol, ethanol and isopropyl alcohol;alkanes such as pentane, hexane and octane; cyclic alkanes such ascyclohexane; aromatic solvents such as benzene, toluene, xylene,mesitylene, tetralin, and diphenylmethane; aliphatic ethers such asethylene glycol, dimethyl ether, ethylene glycol diethyl ether, andpropylene glycol-1-monomthyl ether acetate; aromatic ethers such as1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetol,2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene,2,3-dimethylanisole, and 2,4-dimethylanisole; aliphatic esters such asethyl acetate, n-butyl acetate, ethyl lactate, and n-butyl lactate;aromatic esters such as phenyl acetate, phenyl propionate, methylbenzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate;amide-based solvents such as N,N-dimethylformamide, andN,N-dimethylacetamide; as well as dimethyl sulfoxide, tetrahydrofuran,acetone, chloroform, and methylene chloride. Preferred examples includearomatic solvents, aliphatic esters, aromatic esters, aliphatic ethers,and aromatic ethers.

[Organic Thin Film]

The organic thin film of the present invention is produced by using theorganic electronic material or the ink composition of the presentinvention described above. For example, the organic thin film can beproduced by applying the organic electronic material or the inkcomposition on a desired base material by a known method, such as aninkjet method, a casting method, an immersion method, a printing methodsuch as letterpress printing, intaglio printing, offset printing,planographic printing, letterpress reverse offset printing, screenprinting or gravure printing, or a spin coating method, subsequentlycarrying out a polymerization reaction of the polymer or oligomerthrough light irradiation, a heating treatment or the like, and therebychanging the solubility (curing) of the coated layer. By repeating suchan operation, multilayering of the organic electronic element or organicEL element formed by a coating method can be facilitated.

The coating method such as described above can be carried out usually ata temperature in the range of -20° C. to +300° C., preferably 10° C. to100° C., and particularly preferably 15° C. to 50° C. Furthermore, thereare no particular limitations on the solvent used for the solutiondescribed above, but the same solvents as those used in the inkcomposition may be used.

For the light irradiation, light sources such as a low pressure mercurylamp, a medium pressure mercury lamp, a high pressure mercury lamp, anultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp, afluorescent lamp, a light emitting diode, and sunlight can be used. Theheating treatment can be carried out on a hot plate or in an oven, andcan be carried out at a temperature in the range of 0° C. to +300° C.,preferably 20° C. to 180° C., and particularly preferably 60° C. to 120°C. Particularly, a treatment at 120° C. or below enables the applicationof a resin substrate, so that the production cost of organic electronicelements can be reduced.

Subsequently, an organic electronic material according to a secondembodiment of the present invention will be described.

The organic electronic material according to the second embodiment ofthe present invention is an organic electronic material containing atleast an ionic compound and a compound having a charge transporting unit(hereinafter, referred to as a charge transporting compound), and ischaracterized in that the ionic compound is composed of a counter cationand a counter anion, and the counter cation is any one kind or two ormore kinds of H⁺, a carbocation, a nitrogen cation, an oxygen cation,and a cation having a transition metal.

Since the organic electronic material according to the second embodimentof the present invention contains an ionic compound having a particularcounter cation and an electron transporting compound, lowering of thedriving voltage of the organic electronic element using the material, orstable long-term driving is made possible.

First, the counter cation will be described below.

[Counter Cation]

(Carbocation)

Examples of the carbocation include a primary carbocation, a secondarycarbocation, and a tertiary carbocation. Among these, a secondarycarbocation and a tertiary carbocation are preferred from the viewpointsof the stability of the material and the fact that when these cationsare combined with the anion that will be described below, apolymerization initiator capable of curing at low temperature is formed,and a tertiary carbocation is most preferred. Further examples includetriphenylcarbonium cation, tri(methylphenyl)carbonium cation, andtri(dimethylphenyl)carbonium cation.

(Nitrogen Cation)

Examples of the nitrogen cation include NH₄ ⁺, a primary nitrogencation, a secondary nitrogen cation, a tertiary nitrogen cation, and aquaternary nitrogen cation. Here, the primary nitrogen cation representsa compound in which N⁺ is bonded to three hydrogen ions, and the otherbond is linked to an atom other than hydrogen. The secondary nitrogencation represents a compound in which N⁺ is bonded to two hydrogen ions,and the other bonds are linked to atoms other than hydrogen. Thetertiary nitrogen cation represents a compound in which N⁺ is bonded toone hydrogen ion, and the other bonds are linked to atoms other thanhydrogen. The quaternary ammonium cation represents a compound in whichN⁺ is bonded to atoms other than hydrogen.

Specific examples include ammoniums such as n-butylammonium,dimethylammonium, trimethylammonium, triethylammonium,triisopropylammonium, tri-n-butylammonium, tetramethylammonium,tetraethylammonium, tetra-n-butylammonium,N,N-dimethylcyclohexylammonium, tetramethylammonium,ethyltrimethylammonium, diethyldimethylammonium, triethylmethylammonium,tetraethylammonium, trimethyl-n-propylammonium,trimethylisopropylammonium, trimethyl-n-butylammonium,trimethylisobutylammonium, trimethyl-t-butylammonium,trimethyl-n-hexylammonium, dimethyldi-n-propylammonium,dimethyldiisopropylammonium, dimethyl-n-propylisopropylammonium,methyltri-n-propylammonium, and methyltriisopropylammonium.

Other examples include aniliniums such as N-methylanilinium,N,N-dimethylanilinium, N,N-dimethyl-4-methylanilinium,N,N-diethylanilinium, N,N-diphenylanilinium, andN,N,N-trimethylanilinium.

Further examples include pyridiniums such as pyridinium,N-methylpyridinium, N-butylpyridinium, N-methyl-4-methylpyridinium,N-benzylpyridinium, 3-methyl-N-butylpyridinium, 2-methylpyridinium,3-methylpyridinium, 4-methylpyridinium, 2,3-dimethylpyridinium,2,4-dimethylpyridinium, 2,6-dimethylpyridinium, 3,4-dimethylpyridinium,3,5-dimethylpyridinium, 2,4,6-trimethylpyridinium, 2-fluoropyridinium,3-fluoropyridinium, 4-fluoropyridinium, 2,6-difluoropyridinium,2,3,4,5,6-pentafluoropyridinium, 2-chloropyridinium, 3-chloropyridinium,4-chloropyridinium, 2,3-dichloropyridinium, 2,5-dichloropyridinium,2,6-dichloropyridinium, 3,5-dichloropyridinium,3,5-dichloro-2,4,6-trifluoropyridinium, 2-bromopyridinium,3-bromopyridinium, 4-bromopyridinium, 2,5-dibromopyridinium,2,6-dibromopyridinium, 3,5-dibromopyridinium, 2-cyanopyridinium,3-cyanopyridinium, 4-cyanopyridinium, 2-hydroxypyridinium,3-hydroxypyridinium, 4-hydroxypyridinium, 2,3-dihydroxypyridinium,2,4-dihydroxypyridinium, 2-methyl-5-ethylpyridinium,2-chloro-3-cyanopyridinium, 4-carboxamidopyridinium,4-carboxyaldehydepyridinium, 2-phenylpyridinium, 3-phenylpyridinium,4-phenylpyridinium, 2,6-diphenylpyridinium, 4-nitropyridinium,4-methoxypyridinium, 4-vinylpyridinium, 4-mercaptopyridinium,4-t-butylpyridinium, 2,6-di-t-butylpyridinium, 2-benzylpyridinium,3-acetylpyridinium, 4-ethylpyridinium, pyridinium 2-carboxylate,pyridinium 4-carboxylate, and 2-benzoylpyridinium.

Still further examples include imidazoliums such as imidazolium,1-methyl-imidazolium,1-ethyl-3-methylimidazolium,1-propyl-3-methylimidazolium, 1-butyl-3-methylimidazolium,1-hexyl-3-methylimidazolium, 1-methyl-3-octylimidazolium,1-methyl-N-benzylimidazolium, 1-methyl-3-(3-phenylpropypimidazolium,1-butyl-2,3-dimethylimidazolium, and 1-ethyl-2,3-dimethylimidazolium.

Other examples include pyrrolidiniums such as1-ethyl-l-methylpyrrolidinium and 1-butyl-1-methylpyrrolidinium.

Other examples include quinoliniums such as qunolinium andisoquinolinium. Still other examples include pyrrolidiniums such asN,N-dimethylpyrrolidinium, N-ethyl-N-methylpyrrolidinium, andN,N-diethylpyrrolidinium. Further examples include diimmonium andaminium described in WO 03/005076 and WO 03/097580.

Among these, a tertiary nitrogen cation and a quaternary nitrogen cationare preferred from the viewpoints of stability and the fact that thesecations form initiators capable of curing at low temperature whencombined with the anions that will be described below. A tertiarynitrogen cation is most preferred.

(Oxygen Cation)

Examples of the oxygen cation include trimethyloxonium, triethyloxonium,tripropyloxonium, tributyloxonium, trihexyloxonium, triphenyloxonium,pyrylium, chromenylium, and xanthylium.

(Cation having Transition Metal)

Examples of the cation having a transition metal include Cr compoundssuch as (η5-cyclopentadienyl)(η6-toluene)Cr⁺,(η5-cyclopentadienyl)(η6-xylene)Cr⁺,(η5-cyclopentadienyl)(η6-1-methylnaphthalene)Cr⁺,(η5-cyclopentadienyl)(η6-cumene)Cr⁺,(η5-cyclopentadienyl)(η6-mesitylene)Cr⁺,(η5-cyclopentadienyl)(η6-pyrene)Cr⁺, (η5-fluorenyl)(η6-cumene)Cr⁺,(η5-indenyl)(η6-cumene)Cr⁺, bis(η6-mesitylene)Cr²⁺, bis(η6-xylene)Cr²⁺,bis(η6-cumene)Cr²⁺, bis(η6-toluene)Cr²⁺, (η6-toluene)(η6-xylene)Cr²⁺,(η6-cumene)(η6-naphthalene)Cr²⁺, bis(η5-cyclopentadienyl)Cr⁺,bis(η5-indenyl)Cr⁺, (η5-cyclopentadienyl)(η5-fluorenyl)Cr⁺ and(η5-cyclopentadienyl)(η5-indenyl)Cr⁺; and Fe compounds such as(η5-cyclopentadienyl)(η6-toluene)Fe⁺,(η5-cyclopentadienyl)(η6-xylene)Fe⁺,(η5-cyclopentadienyl)(η6-1-methylnaphthalene)Fe⁺,(η5-cyclopentadienyl)(η6-cumene)Fe⁺,(η5-cyclopentadienyl)(η6-mesitylene)Fe⁺,(η5-cyclopentadienyl)(η6-pyrene)Fe⁺, (η5-fluorenyl)(η6-cumene)Fe⁺,(η5-indenyl)(η6-cumene)Fe⁺, bis(η6-mesitylene)Fe²⁺, bis(η6-xylene)Fe²⁺,bis(η6-cumene)Fe²⁺, bis(η6-toluene)Fe²⁺, (η6-toluene)(η6-xylene)Fe²⁺,(η6-cumene)(η6-naphthalene)Fe²⁺, bis(η5-cyclopentadienyl)Fe²⁺,bis(η5-indenyl)Fe⁺, (η5-cyclopentadienyl)(η5-fluorenyl)Fe⁺ and(η5-cyclopentadienyl)(η5-indenyl)Fe⁺.

[Counter Anion]

The counter anion used in the present invention will be described.

The anion may be any conventionally known anion, and examples thereofinclude halogen ions such as F⁻, Cl⁻, Br⁻, and I⁺; OH⁻; ClO₄ ⁻;sulfonate ions such as FSO₃ ⁻, ClSO₃ ⁻, CH₃SO₃ ⁻, C₆H₅SO₃ ⁻, and CF₃SO₃⁻; sulfate ions such as HSO₄ ⁻ and SO₄ ²—; carbonate ions such as HCO₃ ⁻and CO₃ ²⁻; phosphate ions such as H₂PO₄ ⁻, HPO₄ ²⁻, and PO₄ ³⁻;fluorophosphate ions such as PF₆ ⁻ and PF₅OH⁻; fluorinated alkylfluorophosphate ions such as [(CF₃CF₂)₃PF₃]⁻, [(CF₃CF₂CF₂)₃PF₃]⁻,[((CF₃)₂CF)₃PF₃]⁻, [((CF₃)₂CF)₂PF₄]⁻, [((CF₃)₂CFCF₂)₃PF₃]⁻ and[((CF₃)2CFCF₂)₂PF₄]⁻, borate ions such as BF₄ ⁻, B(C₆F₅)₄ ⁻, andB(C₆H₄CF₃)₄ ⁻, AlCl₄ ⁻, fluoroantimonate ions such as BiF₆, SbF₆ ⁻, andSbF₅OH⁻; and fluoroarsenate ions such as AsF₆ ⁻ and AsF₅OH⁻.

There are no particular limitations on the counter anion used in thepresent invention, but the following structures are preferred from theviewpoints that the lifetime of organic electronic elements islengthened, and that those counter anions form polymerization initiatorscapable of curing at low temperature when combined with the aniondescribed above.

Fluorophosphate ions such as PF₆ ⁻ and PF₅OH⁻; fluorinated alkylfluorophosphate ions such as [(CF₃CF₂)₃PF₃]⁻, [(CF₃CF₂CF₂)₃]⁻,[((CF₃)₂CF)₃PF₃]⁻, [((CF₃)₂CF)₂PF₄]⁻, [((CF₃)₂CFCF₂)₃PF₃]⁻ and[((CF₃)₂CFCF₂)₂PF₄]⁻; borate ions such as BF₄ ⁻, B(C₆F₅)₄ ⁻, andB(C₆H₄CF₃)₄ ⁻; AlCl₄ ⁻; and fluoroantimonate ions such as BiF₆, SbF₆ ⁻,and SbF₅OH⁻ are preferred.

(Ionic Compound) The ionic compound used in the present invention iscomposed of the counter cation and the counter anion described above.There are no particular limitations on this combination; however, fromthe viewpoints that the lifetime of organic electronic elements isextended, and that the ionic compound can be used as an initiatorcapable of curing at low temperature when combined with the aniondescribed above, combinations of a carbonium cation with fluorophosphateions such as PF₆ ⁻ and PF₅OH⁻; borate ions such as BF₄ ⁻, B(C₆F₅)₄ ⁻,and B(C₆H₄CF₃)₄ ⁻; or fluoroantimonate ions such as SbF₆ ⁻ and SbF₅OH⁻;combinations of anilinium with fluorophosphate ions such as PF₆ ⁻ andPF₅OH⁻; borate ions such as BF₄ ⁻, B(C₆F₅)₄ ⁻, and B(C₆H₄CF₃)₄ ⁻; orfluoroantimonate ions such as SbF₆ ⁻ and SbF₅OH⁻ are preferred, whilecombinations of a carbonium cation with borate ions such as B(C₆F₅)₄ ⁻and B(C₆H₄CF₃)₄ ⁻; or fluoroantimonate ions such as SbF₆ ⁻ and SbF₅OH⁻;and combinations of anilinium with borate ions such as B(C₆F₅)₄ ⁻ andB(C₆H₄CF₃)₄ ⁻; or fluoroantimonate ions such as SbF₆ ⁻ and SbF₅OH⁻ aremore preferred.

Specific examples include a salt of a triphenylcarbonium cation and SbF₆⁻, a salt of a triphenylcarbonium cation and B(C₆F₅)₄ ⁻, a salt ofN,N-dimethylanilinium and SbF₆ ⁻, and a salt of N,N-dimethylaniliniumand B(C₆F₅)₄ ⁻.

The ionic compound may be used singly, or two or more kinds may be mixedat any proportion.

[Compound having Charge Transporting Unit (Electron TransportingCompound)]

The term “charge transporting unit” according to the present inventionis an atomic group having an ability to transport holes or electrons,and the details thereof will be described below.

The charge transporting unit may be any moiety having an ability totransport holes or electrons, and there are no particular limitations.However, the charge transporting unit is preferably an amine having anaromatic ring, a carbazole, or a thiophene, and for example, the chargetransporting unit preferably has a partial structure represented by oneof the following formulas (la) to (7a).

(wherein Ar₁ to Ar₂₀ each independently represent an aryl group orheteroaryl group having 2 to 30 carbon atoms, or a substituted orunsubstituted arylene group or heteroarylene group. Here, the aryl groupis an atomic group obtained by excluding one hydrogen atom from anaromatic hydrocarbon, and a heteroaryl group represents an atomic groupobtained by excluding one hydrogen atom from an aromatic compound havinga heteroatom, or R. R's each independently represent —R¹, —OR², —SR³,—OCOR⁴, —COOR⁵, —SiR⁶R⁷R⁸, or one of the formulas (2a) to (4a) (whereinR¹ to R⁸ each represent a hydrogen atom, a linear, cyclic or branchedalkyl group having 1 to 22 carbon atoms, or an aryl group or heteroarylgroup having 2 to 30 carbon atoms.). Here, the arylene group is anatomic group obtained by excluding two hydrogen atoms from an aromatichydrocarbon, and a heteroarylene group is an atomic group obtained byexcluding two hydrogen atoms from an aromatic compound having aheteroatom. X represents a group obtained by further removing onehydrogen atom from a group having one or more hydrogen atoms selectedamong the groups represented by R.)

Furthermore, the charge transporting compound according to the presentinvention is preferably a polymer or an oligomer, from the viewpoints ofsolubility and film-forming properties. Further, the polymer or oligomerpreferably contains a repeating unit represented by one of the followingformulas.

In the formulas shown above, Ar₁ to Ar₁₀₀ each independently representan aryl group or heteroaryl group having 2 to 30 carbon atoms, or asubstituted or unsubstituted arylene group or heteroarylene group. Here,the aryl group is an atomic group obtained by excluding one hydrogenatom from an aromatic hydrocarbon, and a heteroaryl group represents anatomic group obtained by excluding one hydrogen atom from an aromaticcompound having a heteroatom. R's each independently represent —R¹,—OR², —SR³, —OCOR⁴, —COOR⁴, —SiR⁶R⁷R⁸, or one of the formulas (2a) to(4a) (wherein R¹ to R⁸ each represent a hydrogen atom, a linear, cyclicor branched alkyl group having 1 to 22 carbon atoms, or an aryl group orheteroaryl group having 2 to 30 carbon atoms.) Here, the arylene groupis an atomic group obtained by excluding two hydrogen atoms from anaromatic hydrocarbon, and a heteroarylene group is an atomic groupobtained by excluding two hydrogen atoms from an aromatic compoundhaving a heteroatom. X represents a group obtained by further removingone hydrogen atom from a group having one or more hydrogen atomsselected among the groups represented by R. Y represents a trivalentsubstituent, and Z represents a divalent substituent. Further, xrepresents an integer of 1 or greater.

Furthermore, the polymer or oligomer preferably has one or more“polymerizable substituent” so as to change the solubility. Here,“polymerizable substituent” is a substituent which is capable of formingan intermolecular bond between two or more molecules through apolymerization reaction, and specific examples thereof are the same asthe polymerizable substituents of the polymer or oligomer previouslydescribed in connection with the first embodiment of the presentinvention. According to the second embodiment, any of oxetane, epoxy andvinyl ether is preferred.

The polymer or oligomer that forms the polymerized layer according tothe present invention may also be a copolymer having the above-describedarylene group or heteroarylene group, or the structure represented byany of the formulas, as a copolymerization repeating unit in addition tothe repeating units described above, for the purpose of regulating thesolubility, heat resistance or electrical properties. In this case, thecopolymer may be a random, block or graft copolymer, or may also be apolymer having an intermediate structure, for example, a randomcopolymer having the characteristics of a block copolymer. The polymeror oligomer used in the present invention may have branches in the mainchain, and may therefore have three or more chain ends.

According to the present invention, it is preferable that the ioniccompound previously described be an electron-accepting compound, and thecharge transporting compound be possibly one-electron oxidized by thationic compound. It is because when the charge transporting compound isoxidized, the carrier injection properties at the anode are improved,and it is useful for low voltage driving of the organic electronicelement.

(Solvent)

Examples of the solvent used in the present invention includechloroform, methylene chloride, dichloroethane, tetrahydrofuran,toluene, xylene, mesitylene, anisole, phenetol, acetone, methyl ethylketone, ethyl acetate, butyl acetate, ethyl acetate, n-butyl acetate,ethyl lactate, n-butyl lactate, y-butyrolactone, ethylcellosolveacetate, phenyl acetate, phenyl propionate, methyl benzoate, ethylbenzoate, propyl benzoate, n-butyldiphenylmethane benzoate, diphenylether, N,N-dimethylformamide, N,N-dimethylacetamide, and ethylene glycoldimethyltetralin. Any one of these may be used singly, or two or morekinds may be used in any combination and at any proportion.

(Ratio)

The mixing ratio of the ionic compound is preferably from 0.01 parts bymass to 50 parts by mass, more preferably from 0.05 parts by mass to 25parts by mass, and particularly preferably from 0.1 parts by mass to 20parts by mass, when 100 parts by mass of the charge transportingcompound is used. If the mixing ratio of the ionic compound is less than0.01 parts by mass, the effect of decreasing the driving voltage is notobtained, and if the mixing ratio is more than 50 parts by mass, thedriving voltage tends to increase.

When the ionic compound is used as a polymerization initiator, themixing ratio is preferably from 0.1 parts by mass to 50 parts by massrelative to 100 parts by mass of the compound having a polymerizablesubstituent. If the mixing ratio is less than 0.1 parts by mass,polymerization does not sufficiently proceed. If the mixing ratio ismore than 50 parts by mass, there is a problem that the film quality isdeteriorated. In regard to the polymerization method using the ioniccompound as a polymerization initiator, it is preferable to initiate thepolymerization only by heating.

(Other Components)

The ionic compound has both the function of a polymerization initiatorand the function of an electron acceptor. These may be used singly, orplural agents may be used in combination. Furthermore, the material mayalso contain a polymerization initiator or an electron acceptor otherthan those belonging to the scope of the present invention. Ifnecessary, the material may further contain a crosslinking material or aluminescent material.

[Method for Forming Thin Film]

In order to form various layers that are used an in organic electronicelement or the like using the organic electronic material of the presentinvention, for example, the formation can be carried out by applying asolution containing the organic electronic material of the presentinvention on a desired base material by a known method such as, forexample, an inkjet method, a casting method, an immersion method, aprinting method such as letterpress printing, intaglio printing, offsetprinting, planographic printing, letterpress reverse offset printing,screen printing or gravure printing, or a spin coating method,subsequently carrying out a polymerization reaction through lightirradiation, a heating treatment or the like, and thereby changing thesolubility (curing) of the coated layer. By repeating such an operation,multilayering of the organic electronic element or organic EL elementformed by a coating method, can be facilitated.

[Substrate]

As the substrate that can be used in the organic EL element of thepresent invention, there are no particular limitations on the kind ofglass, plastics and the like, and there is no particular restriction aslong as the substrate is transparent. However, glass, quartz, alight-transmissive resin film or the like is used with preference. Whena resin film is used, the organic EL element can be imparted withflexibility, which is particularly preferable.

Examples of the resin film include films formed from polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone(PES), polyether imide, polyether ether ketone, polyphenylene sulfide,polyallylate, polyimide, polycarbonate (PC), cellulose triacetate (TAC),cellulose acetate propionate (CAP) and the like.

Furthermore, when a resin film is used, the resin film may be used aftercoating the film with an inorganic substance such as silicon oxide orsilicon nitride, in order to suppress penetration of water vapor, oxygenor the like.

[Organic EL Element]

The organic EL element of the present invention has a layer formed fromthe organic electronic material of the first embodiment or the secondembodiment of the present invention (hereinafter, also referred to as anorganic thin film (polymerized layer)). In other words, the organic ELelement is characterized by including the organic thin film of thepresent invention. The organic EL element of the present invention isnot particular limited as long as the element includes a light emittinglayer, an anode, a cathode and a substrate, and may also have otherlayers such as a hole injection layer, an electron injection layer, ahole transport layer, and an electron transport layer. Any of the lightemitting layer, hole injection layer, electron injection layer, holetransport layer and electron transport layer may be the organic thinfilm of the present invention. Hereinafter, the various layers will bedescribed in detail.

[Light Emitting Layer]

The material used in the light emitting layer may be a low molecularweight compound, or may be a polymer or an oligomer, and a dendrimer orthe like can also be used. In the case of a polymer or an oligomer, itis preferable because the polymer or oligomer has high solubility insolvents and a coating type production method can be applied. Examplesof a low molecular weight compound utilizing fluorescent light emissioninclude perylene, coumarin, rubrene, quinacridone, dyes for dye lasers(for example, rhodamine, and DCMl), aluminum complexes (for example,tris(8-hydroxyquinolinato)aluminum(III) (Alq₃)), stilbene, andderivatives thereof. As a polymer or oligomer utilizing fluorescentlight emission, polyfluorene, polyphenylene, polyphenylenevinylene(PPV), polyvinylcarbazole (PVK), a fluorene-benzothiadiazole copolymer,a fluorene-triphenylamine copolymer, and derivatives or mixtures thereofcan be suitably used.

On the other hand, due to a demand for an improvement of the efficiencyof organic EL elements in recent years, the development ofphosphorescent organic EL elements is also actively underway. In aphosphorescent organic EL element, it is possible to utilize the energyof the singlet state as well as the energy of the triplet state, and theinternal quantum yield can, in principle, be increased up to 100%. Inthe phosphorescent organic EL element, phosphorescent light emission isextracted by doping a host material with a metal complex-basedphosphorescent material containing a heavy metal such as platinum oriridium, as a dopant emitting phosphorescent light (see M. A. Baldo etal., Nature, Vol. 395, p. 151 (1998); M. A. Baldo et al., AppliedPhysics Letters, Vol. 75, p. 4 (1999); or M. A. Baldo et al., Nature,Vol. 403, p. 750 (2000)).

Also for the organic EL element of the present invention, it ispreferable to use a phosphorescent material in the light emitting layerfrom the viewpoint of increasing the efficiency. In a phosphorescentorganic EL element using a phosphorescent material, it is possible toutilize the energy of the singlet state as well as the energy of thetriplet state, and the internal quantum yield can in principle beincreased up to 100%. In the phosphorescent organic EL element,phosphorescent light emission is extracted by doping a host materialwith a metal complex-based phosphorescent material containing a heavymetal such as platinum or iridium, as a dopant emitting phosphorescentlight (see M. A. Baldo et al., Nature, Vol. 395, p. 151 (1998); M. A.Baldo et al., Applied Physics Letters, Vol. 75, p. 4 (1999); or M. A.Baldo et al., Nature, Vol. 403, p. 750 (2000)).

As the phosphorescent material, a metal complex containing a centralmetal such as Ir or Pt can be suitably used. Specific examples include,as Ir complexes, FIr(pic) [iridium(III)bis[(4,6-difluorophenyl)-pyridinato-N,C²]picolinate] emitting bluelight; Ir(ppy)₃ [fac-tris(2-phenylpyridine)iridium] emitting green light(see Non-Patent Document 4 described above); and (btp)₂Ir(acac){bis[2-(2′-benzo[4,5-α]thienyl)pyridinato-N,C3]iridium(acetylacetonate)} and Ir(piq)₃ [tris(1-phenylisoquinoline)iridium]emitting red light, which are shown in Adachi et al., Appl. Phys. Lett.,78, No. 11, p. 1622 (2001).

Examples of a Pt complex include2,3,7,8,12,13,17,18-octaethyl-21H,23H-phorphine platinum (PtOEP)emitting red light.

As the phosphorescent material, low molecular weight or dendridecompounds, for example, an iridium-cored dendrimer, can be used.Further, derivatives thereof can also be suitably used.

When a phosphorescent material is contained in the light emitting layer,it is preferable that the light emitting layer contain a host materialin addition to the phosphorescent material.

The host material may be a low molecular weight compound or may be apolymeric compound, and a dendrimer or the like can also be used.

Examples of the low molecular weight compound include CBP(4,4′-bis(9H-carbazol-9-yl)biphenyl), mCP(1,3-bis(9-carbazolyl)benzene), and CDBP(4,4′-bis(carbazol-9-yl)-2,2′-dimethylbiphenyl). The polymeric compoundmay be the polymer or oligomer of the present invention, orpolyvinylcarbazole, polyphenylene, polyfluorene and the like can beused, and derivatives thereof can also be used.

The light emitting layer may be formed by a vapor deposition method, ormay be formed by a coating method.

In the case of forming the light emitting layer by a coating method, itis more preferable because the organic EL element can be produced at lowcost. When the light emitting layer is formed according to a coatingmethod, the formation can be carried out by applying a solutioncontaining a phosphorescent material and if necessary, a host material,on a desired base material by a known method such as, for example, aninkjet method, a casting method, an immersion method, a printing methodsuch as letterpress printing, intaglio printing, offset printing,planographic printing, letterpress reverse offset printing, screenprinting or gravure printing, or a spin coating method.

The coating method such as described above can be carried out at atemperature in the range of usually -20° C. to +300° C., preferably 10°C. to 100° C., and particularly preferably 15° C. to 50° C. Further, forthe light irradiation process, a light source such as a low pressuremercury lamp, a medium pressure mercury lamp, a high pressure mercurylamp, an ultra-high pressure mercury lamp, a metal halide lamp, a xenonlamp, a fluorescent lamp, a light emitting diode, or sunlight can beused. There are no particular limitations on the solvent used in thesolution described above, but examples include chloroform, methylenechloride, dichloroethane, tetrahydrofuran, toluene, xylene, mesitylene,anisole, acetone, methyl ethyl ketone, ethyl acetate, butyl acetate,ethylcellosolve acetate, diphenylmethane, diphenyl ether, and tetralin.Furthermore, the heating treatment after coating can be carried out on ahot plate or in an oven, and can be carried at a temperature in therange of 0° C. to +300° C., preferably 20° C. to 250° C., morepreferably 50° C. to 200° C., and even more preferably 70° C. to 150° C.When the temperature is low, the curing reaction cannot proceedsufficiently, and since there is a problem that residual solventremains, the lifetime of the organic electronic element decreases. Whenthe temperature is high, it is difficult to produce the organicelectronic element on a resin substrate.

It is preferable that the curing reaction after coating be carried outonly by a heating treatment, so as to achieve an extension of thelifetime of the organic electronic element.

[Organic Thin Film (Polymerized Layer)]

Next, the layer formed by using a mixture containing the organicelectronic material of the present invention, that is, the organic thinfilm, will be described in detail. The layer formed by using a mixturecontaining the organic electronic material of the present invention(polymerized layer) is, specifically, a layer obtained by applying amixture containing the organic electronic material of the presentinvention on a desired base material by the coating method describedabove for the method for forming a thin film, subsequently carrying outa polymerization reaction of the polymerizable substituent carried bythe polymer or oligomer through light irradiation, a heating treatmentor the like, and thereby changing the solubility of the coated layer(curing), that is, making the layer insoluble. As such, when apolymerization reaction of the polymerizable substituent carried by thepolymer or oligomer is carried out, and thereby the solubility of thecoated layer is changed (cured), the thermal stability of the layer canbe improved.

Furthermore, when the solubility is decreased by the polymerizationreaction, even in the case of further applying and forming another layersuch as a light emitting layer, a hole transport layer, an electrontransport layer or an electron injection layer, the organic thin film(polymerized layer) is not dissolved by the coating liquid, andtherefore, this other layer can be formed by a coating method. That is,since a multilayer structure can be easily produced by a coating method,an organic EL element having high efficiency and a long lifetime can beproduced at low cost. According to the second embodiment, the chargetransporting compound used in the polymerized layer is preferably apolymer or oligomer containing a repeating unit having hole transportproperties, from the viewpoint of the uniformity of the film.

The organic thin film (polymerized layer) can be used as a holeinjection layer, a hole transport layer, a light emitting layer, anelectron transport layer, or an electron injection layer of an organicEL element, and from the viewpoints of light emission efficiency andlifetime characteristics, the organic thin film is particularlypreferably a hole injection layer, a hole transport layer, an electrontransport layer, or an electron injection layer.

In the organic EL element of the present invention, any one layer may bethe organic thin film (polymerized layer), or plural layers or all thelayers may be polymerized layers. Furthermore, although there are noparticular limitations on the film thickness of these layers, from theviewpoint of reducing the influence of the surface unevenness of thesubstrate or the lower layer and reducing the influence of the dust orthe like adhering to the substrate or the surface of the lower layer,the thickness in the case of a hole injection layer, a hole transportlayer, an electron injection layer or an electron transport layer ispreferably 10 to 100 nm, more preferably 15 to 90 nm, and even morepreferably 20 to 80 nm. If the thickness is smaller than 10 nm, theorganic thin film cannot fill up the surface unevenness of the substrateor the lower layer, and the organic thin film may cause layers that areoriginally not adjacent to each other to be short-circuited, or becomesusceptible to the influence of dust or the like on the substrate or onthe surface of the lower layer. Furthermore, if the thickness is largerthan 100 nm, a decrease in the light extraction efficiency or anincrease in the driving voltage may occur easily. On the other hand, inthe case of a light emitting layer, the thickness is preferably 10 to200 nm, more preferably 15 to 190 nm, and even more preferably 20 to 180nm. If the thickness is smaller than this range, a sufficient lightemission intensity cannot be obtained, and if the thickness is largerthan this range, the driving voltage is prone to increase.

Furthermore, the organic thin film (polymerized layer) is morepreferably laminated to be adjacent to a light emitting layer containinga phosphorescent material. This is because the organic thin film hasless influence on the light emission efficiency and deterioration of thephosphorescent material, and can improve the light emission efficiencyof the element or the element lifetime.

[Cathode]

The cathode material is preferably, for example, a metal such as Li, Ca,Mg, Al, In, Cs, Ba, Mg/Ag, LiF, or CsF, or a metal alloy.

[Anode]

For the anode, a metal (for example, Au), or another material having theelectrical conductivity of a metal, for example, an oxide (for example,ITO: indium oxide/tin oxide), or a conductive polymer (for example, apolythiophene-polystyrene sulfonate mixture (PEDOT: PSS)) can be used.

[Electron Transport Layer and Electron Injection Layer]

Examples of the electron transport layer and the electron injectionlayer include phenanthroline derivatives (for example,2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP)), bipyridinederivatives, nitro-substituted fluorene derivatives, diphenylquinonederivatives, thiopyrane dioxide derivatives, heterocyclictetracarboxylic acid anhydrides such as naphthaleneperylene,carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethaneand anthrone derivatives, oxadiazole derivatives(2-(4-biphenylyl)-5-(4-t-butylphenyl-1,3,4-oxadiazole (PBD)), andaluminum complexes (for example, tris(8-hydroxyquinolinato)aluminum(III)(Alq₃)). Furthermore, thiadiazole derivatives obtained by substitutingthe oxygen atom of an oxadiazole ring in the oxadiazole derivatives witha sulfur atom, and quinoxaline derivatives having a quinoxaline ring,which is known as an electron-withdrawing group, can also be used. Apolymer or oligomer according to the present invention, having a partialstructure of the derivatives described above, can also be used.

[Emission Color]

There are no particular limitations on the emission color for theorganic EL element of the present invention, but a white light emittingelement is preferred because it can be used in various lightinginstruments for home lighting, automobile interior lighting, andbacklights for clocks and liquid crystal displays.

In regard to the method for forming a white light emitting element,since it is difficult for the present to obtain white light emissionusing a single material, white light emission is obtained bysimultaneously emitting plural emission colors using plural lightemitting materials and thereby mixing the colors. There are noparticular limitations on the combination of plural emission colors, buta combination including three maximum emission wavelengths of blue,green and red colors, and a combination including two maximum emissionwavelengths using the relationships of complementary colors such as blueand yellow, or yellow-green and orange, may be used. Furthermore, thecontrol of the emission color can be carried out by adjusting the typeand amount of the phosphorescent material.

<Display Element, Lighting Device, and Display Device>

The display element of the present invention is characterized byincluding the organic EL element of the present invention previouslydescribed.

For example, a color display element may be obtained by using theorganic EL element of the present invention as an element correspondingto each pixel of red, green and blue (RGB).

In regard to the formation of images, a simple matrix type system inwhich individual organic EL elements arranged in a panel are directlydriven by electrodes disposed in a matrix form, and an active matrixtype system in which a thin film transistor is disposed in each elementare available. The former involves a simple structure, but since thereis a limitation on the number of vertical pixels, the former system isused for the display of characters and the like. The latter workssatisfactorily even if the driving voltage is low and the current issmall, and bright high-definition images are obtained. Therefore, thelatter system is used for high resolution displays.

Furthermore, the lighting device of the present invention ischaracterized by including the organic EL element of the presentinvention previously described. The display device of the presentinvention is characterized by including the lighting device and a liquidcrystal element as a display unit. The display device may be a displaydevice which uses the lighting device of the present invention as abacklight (white emission color source) and uses a liquid crystalelement as a display unit, that is, a liquid crystal display device.This constitution is a constitution in which, in a known liquid crystaldisplay device, only the backlight is replaced with the lighting deviceof the present invention, and the liquid crystal element part can beproduced by diverting known technologies.

EXAMPLES

Hereinafter, the present invention will be more specifically describedby way of Examples, but the present invention is not intended to belimited to the following Examples.

(Synthesis of Monomer A)

3-Ethyl-3-hydroxymethyloxetane (50 mmol), 4-bromobenzyl bromide (50mmol), n-hexane (200 mL), tetrabutylammonium bromide (2.5 mmol) and a 50wt % aqueous solution of sodium hydroxide (36 g) were introduced into around bottom flask, and the mixture was heated and stirred for 6 hoursat 70° C. under nitrogen.

After the mixture was cooled to room temperature (25° C.), 200 mL ofwater was added thereto, and the resulting mixture was extracted withn-hexane. The solvent was distilled off, and then the residue waspurified by silica gel column chromatography and distillation underreduced pressure. Thus, 9.51 g of a monomer A having a polymerizablesubstituent was obtained as a colorless oily substance. Yield 67%.

¹H-NMR(300 MHz, CDCl₃, δppm); 0.86(t, J=7.5 Hz, 3H), 1.76(t, J=7.5 Hz,2H), 3.57(s, 2H), 4.39(d, J=5.7 Hz, 2H), 4.45(d, J=5.7 Hz, 2H), 4.51(s,2H), 7.22(d, J=8.4 Hz, 2H), 7.47(d, J=8.4 Hz, 2H).

The reaction scheme of the present Synthesis Example is presented below.

(Synthesis of Monomer B)

1,6-dibromohexane (73.2 g, 0.3 mol) and 3-ethyl-3-hydroxyoxetane(Toagosei Co., Ltd., OXT-101) (11.6 g, 0.1 mol) were dissolved in 400 mLof n-hexane, and tetrabutylammonium bromide (1.62 g, 4.9 mmol) and 100 gof a 45% aqueous solution of sodium hydroxide were added to thesolution. The mixture was heated to reflux for 6 hours. After completionof the reaction, 200 mL of water was added to the reaction mixture, andthe organic layer was separated. The aqueous layer was extracted threetimes with n-hexane, and the extract was combined with the organic layerinitially separated. The organic layer was dried over anhydrous sodiumsulfate. The solvent was distilled off with an evaporator, and1,6-dibromohexane was distilled off by distillation under reducedpressure (3 to 10 mmHg, 110° C.). Thus,3-(6-bromohexyloxymethyl)-3-ethyloxetane was obtained as a colorlessoily substance (25.0 g, yield 89.7%).

The reaction scheme of the above reaction is presented below.

p-bromobenzyl alcohol (16.4 g, 0.088 mol) and3-(6-bromohexyloxymethyl)-3-ethyloxetane (22.2 g, 0.080 mol) weredissolved in 320 mL of n-hexane, and tetrabutylammonium bromide (1.29 g,4.0 mmol) and 80 g of a 45% aqueous solution of sodium hydroxide wereadded to the solution. The mixture was heated to reflux for 9 hours.After completion of the reaction, 200 mL of water was added thereto, andthe organic layer was separated and was dried over anhydrous sodiumsulfate. The solvent was distilled off with an evaporator, and a crudeproduct thus obtained was purified by silica gel column chromatography(filler: Wakogel (registered trademark) C-300HG mobile phase: n-hexane :ethyl acetate=4:1). Thus,3-(6-(p-bromobenzyloxy)hexyloxymethyl)-3-ethyloxetane was obtained as acolorless oily substance (18.4 g, yield 60.2%).

The reaction scheme of the above reaction is presented below.

(Preparation of Pd Catalyst)

In a glove box under a nitrogen atmosphere,tris(dibenzylideneacetone)dipalladium (73.2 mg, 80 μmol) was weighed ina sample tube at room temperature, anisole (15 mL) was added thereto,and the mixture was stirred for 30 minutes. Similarly,tris(t-butyl)phosphine (129.6 mg, 640 μmol) was weighed in a sampletube, anisole (5 mL) was added thereto, and the mixture was stirred for5 minutes. These solutions were mixed and stirred at room temperaturefor 30 minutes. The resultant was used as a catalyst.

Oligomer Synthesis Example 1

In a sealable container made of a fluororesin, tris(4-bromophenyl)amine(0.3 mmol) as a monomer 1,1,4-bis(4,4,5,5-tetramethyl-1,3-dioxa-2-boracyclopentan-2-yl)benzene(0.4 mmol) as a monomer 2, the monomer A having a polymerizablesubstituent (0.1 mmol), tetrakis(triphenylphosphine)palladium (0.008mmol), a 2 M aqueous solution of potassium carbonate (5.3 mL), Aliquat336 (0.4 mmol), and anisole (4 mL) were introduced. In a nitrogenatmosphere, the mixture was irradiated with microwaves in the sealedcontainer, and was heated and stirred for 2 hours at 90° C.

The reaction solution was poured into a methanol/water mixed solvent(9:1), and a polymer thus precipitated was separated by filtration. Theprecipitate thus obtained was filtered by suction and dissolved intoluene, and triphenylphosphine, polymer-bound, on styrenedivinylbenzene copolymer (Strem Chemicals, Inc., 200 mg per 100 mg ofthe polymer) was added thereto. The resulting mixture was stirredovernight. After completion of stirring, the triphenylphosphine, polymerbound, on styrene-divinylbenzene copolymer and insoluble matter wereremoved by filtration, and the filtrate was concentrated with a rotaryevaporator. The residue was dissolved in toluene and was reprecipitatedfrom methanol-acetone (8:3). The precipitate thus generated was filteredby suction, and was washed with methanol-acetone (8:3). The precipitatethus obtained was dried in a vacuum, and a polymer was obtained. Thus,an oligomer A was obtained. The number average molecular weight of theoligomer A thus obtained was 4652 relative to polystyrene standards.

The reaction scheme of the present Synthesis Example is presented below.

Oligomer Synthesis Example 2

Monomer 1 (0.6 mmol), monomer 3 (1.8 mmol), monomer 4 (0 mmol), monomerB (1.8 mmol), the structures of which are all shown below, and anisole(20 mL) were introduced into a three-necked round bottom flask, and aprepared Pd catalyst solution (2.5 mL) was further added thereto. Themixture was stirred for 30 minutes, and then a 10% aqueous solution oftetraethylammonium hydroxide (12 mL) was added to the mixture. All thesolvents were used after being degassed by nitrogen bubbling for 30minutes or longer. This mixture was heated to reflux for 2 hours. Theentire operation to this stage was carried out under a nitrogen gasstream.

After completion of the reaction, the organic layer was washed withwater, and the organic layer was poured into methanol-water (9:1). Aprecipitated thus generated was filtered by suction and was washed withmethanol-water (9:1). A precipitate thus obtained was dissolved intoluene, and was reprecipitated from methanol. The precipitate thusobtained was filtered by suction and was dissolved in toluene.Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer(Strem Chemicals, Inc., 200 mg per 100 mg of the polymer) was added tothe solution, and the resulting mixture was stirred overnight. Aftercompletion of stirring, the triphenylphosphine, polymer-bound, onstyrene-divinylbenzene copolymer and insoluble matter were removed byfiltration, and the filtrate was concentrated with a rotary evaporator.The residue was dissolved in toluene, and then was reprecipitated frommethanol-acetone (8:3). A precipitate thus generated was filtered bysuction, and was washed with methanol-acetone (8:3). The precipitatethus obtained was dried in a vacuum, and thus a polymer was obtained.The molecular weight was measured by GPC (relative to polystyrenestandards) using THF as an eluent. The molecular weight and yield areindicated in Table 1.

Oligomer Synthesis Example 3

An oligomer 3 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.4 mmol), monomer 3 (2.0 mmol), monomer 4 (0.8 mmol), andmonomer B (1.2 mmol). The molecular weight and yield are indicated inTable 1.

Oligomer Synthesis Example 4

An oligomer 4 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.7 mmol), monomer 3 (1.75 mmol), and monomer B (1.4 mmol).The molecular weight and yield are indicated in Table 1.

Oligomer Synthesis Example 5

An oligomer 5 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.6 mmol), monomer 3 (1.8 mmol), monomer 4 (0.3 mmol), andmonomer B (1.2 mmol). The molecular weight and yield are indicated inTable 1.

Oligomer Synthesis Example 6

An oligomer 6 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.9 mmol), monomer 3 (2.1 mmol), and monomer B (1.5 mmol).The molecular weight and yield are indicated in Table 1.

Oligomer Synthesis Example 7

An oligomer 7 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.75 mmol), monomer 3 (2.25 mmol), monomer 4 (0.5 mmol), andmonomer B (1.25 mmol). The molecular weight and yield are indicated inTable 1.

TABLE 1 Monomer ratios, molecular weights and yields of synthesizedoligomers Monomer ratios Monomer 1:monomer 3:monomer 4:monomer B Mw Mnyields (%) Oligomer 2 1:3:0:3 13300 3500 62.3 Oligomer 3 1:5:2:3 170004500 66.7 Oligomer 4 2:5:0:4 31000 7800 72.2 Oligomer 5 2:6:1:4 330009200 75 Oligomer 6 3:7:0:5 105000 18000 65.9 Oligomer 7 3:9:2:5 11400023000 66.3

A higher ratio of the monomer 1, which is a monomer for forming abranched structure, results in a higher molecular weight. In theoligomers 2 and 3, the yield decreased because the low molecular weightcomponents were removed by reprecipitation. In the oligomers 6 and 7, atendency of decreased yield was observed because components that wereinsoluble in toluene were produced.

Oligomer Synthesis Example 8

An oligomer 8 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 5 shown below (0.7 mmol), monomer 3 shown below (1.75 mmol), andmonomer B (1.4 mmol). The molecular weight measured by GPC (relative topolystyrene standards) was Mw=64000 and Mn=15900, and the yield was56.9%.

Oligomer Synthesis Example 9

An oligomer 9 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 6 shown below (0.6 mmol), monomer 3 shown below (2 1 mmol), andmonomer B (1.8 mmol). The molecular weight measured by GPC (relative topolystyrene standards) was Mw=18900 and Mn=4200, and the yield was67.2%.

Oligomer Synthesis Example 10

An oligomer 10 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 7 shown below (0.7 mmol), monomer 3 shown below (1.75 mmol), andmonomer B (1.4 mmol). The molecular weight measured by GPC (relative topolystyrene standards) was Mw=12700 and Mn=3600, and the yield was51.2%.

Oligomer Synthesis Example 11

An oligomer 11 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 8 shown below (0.6 mmol), monomer 3 shown below (2.1 mmol), andmonomer B (1.8 mmol). The molecular weight measured by GPC (relative topolystyrene standards) was Mw=14000 and Mn=2700, and the yield was51.2%.

Oligomer Synthesis Example 12

An oligomer 12 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 shown below (0.7 mmol), monomer 9 shown below (1.75 mmol), andmonomer B (1.4 mmol). The molecular weight and yield are indicated inTable 2.

Oligomer Synthesis Example 13

An oligomer 13 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.9 mmol), monomer 9 (2.1 mmol), and monomer B (1.5 mmol).The molecular weight and yield are indicated in Table 2.

Oligomer Synthesis Example 14

An oligomer 14 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 1 (0.75 mmol), monomer 9 (2.25 mmol), monomer 10 (0.5 mmol), andmonomer B (1.25 mmol). The molecular weight and yield are indicated inTable 2.

TABLE 2 Monomer ratios, molecular weights and yields of synthesizedoligomers Monomer ratio Monomer 1:monomer 9:monomer 10:monomer B Mw MnYield (%) Oligomer 12 2:5:0:4 68800 9200 67.1 Oligomer 13 3:7:0:5 9040015800 69.8 Oligomer 14 3:9:2:5 92000 19800 66.6

Oligomer Synthesis Example 15

An oligomer 15 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 7 shown below (0.7 mmol), monomer 11 shown below (1.75 mmol),and monomer B (1.4 mmol). The molecular weight measured by GPC (relativeto polystyrene standards) was Mw=9100 and Mn=2500, and the yield was42.7%.

Oligomer Synthesis Example 16

An oligomer 11 was synthesized in the same manner as in OligomerSynthesis 1 Example 2, except that the monomers added were replaced bymonomer 12 (0.6 mmol), monomer 13 (2.1 mmol), and monomer B (1.8 mmol).The molecular weight measured by GPC (relative to polystyrene standards)was Mw=17800 and Mn=4500, and the yield was 48.7%.

Oligomer Synthesis Example 17

An oligomer 17 was synthesized in the same manner as in OligomerSynthesis Example 2, except that the monomers added were replaced bymonomer 6 (0.75 mmol), monomer 9 (2.25 mmol), monomer 14 (0.5 mmol), andmonomer B (1.25 mmol). The molecular weight measured by GPC (relative topolystyrene standards) was Mw=20700 and Mn=3300, and the yield was56.1%.

Oligomer Synthesis Example 18

In a three-necked round bottom flask, monomer 6 shown below (0.6 mmol),monomer 15 shown below (2.1 mmol), monomer B (1.9 mmol), and anisole (20mL) were introduced, and a prepared Pd catalyst solution (5.0 mL) wasfurther added thereto. The mixture was stirred for 30 minutes, and thenNaOBu (5.0 mmol) was added. All the solvents were used after beingdegassed by nitrogen bubbling for 30 minutes or longer. This mixture washeated to reflux for 6 hours. The entire operation to this stage wascarried out under a nitrogen gas stream.

After completion of the reaction, the organic layer was washed withwater, and the organic layer was poured into methanol-water (9:1). Aprecipitate thus generated was filtered by suction, and was washed withmethanol-water (9:1). The precipitate thus obtained was dissolved intoluene, and was reprecipitated from methanol. The precipitate thusobtained was filtered by suction, and was dissolved in toluene.Triphenylphosphine, polymer-bound on styrene-divinylbenzene copolymer(Strem Chemicals, Inc., 200 mg per 100 mg of the polymer) was added tothe solution, and the mixture was stirred overnight. After completion ofstirring, the triphenylphosphine, polymer-bound onstyrene-divinylbenzene copolymer and insoluble matter were removed byfiltration, and the filtrate was concentrated with a rotary evaporator.The residue was dissolved in toluene, and then was reprecipitated frommethanol-acetone (8:3). A precipitate thus generated was filtered bysuction, and was washed with methanol-acetone (8:3). The precipitatethus obtained was dried in a vacuum. The molecular weight measured byGPC (relative to polystyrene standards) was Mw=23000 and Mn=4600, andthe yield was 65.1%.

(Comparative Oligomer 1: no Polymerizable Substituent)

A comparative oligomer 1 was synthesized in the same manner as inOligomer Synthesis Example 2, except that the monomers added werereplaced by monomer 1 shown below (0.7 mmol), monomer 3 shown below(1.75 mmol), and monomer 16 shown below (1.4 mmol). The molecular weightmeasured by GPC (relative to polystyrene standards) was Mw=77000 andMn=12400, and the yield was 65.5%.

Comparative Example Oligomer 2 No Branched Structure 1

A comparative oligomer 2 was synthesized in the same manner as inOligomer Synthesis Example 2, except that the monomers added werereplaced by monomer 3 shown below (2.0 mmol), monomer 4 shown below (1.6mmol), and monomer B shown below (0.8 mmol). The molecular weightmeasured by GPC (relative to polystyrene standards) was Mw =10200 andMn=6700, and the yield was 60.8%.

Comparative Example Oligomer 3 No Branched Structure 2

A comparative oligomer 3 was synthesized in the same manner as inOligomer Synthesis Example 2, except that the monomers added werereplaced by monomer 17 shown below (2.0 mmol), monomer 15 shown below(1.6 mmol), and monomer B shown below (0.8 mmol). The molecular weightmeasured by GPC (relative to polystyrene standards) was Mw =2800 andMn=1600, and the yield was 13.2%.

(Evaluation of Polymerizability)

A coating solution prepared by mixing a toluene solution (400 μL) of anoligomer (4.5 mg) and a toluene solution (100 μL) of an ionic compound 1(0.45 g) represented by the following formula, was spin coated on aquartz plate at 3000 rpm. Subsequently, the quartz plate was heated on ahot plate at 90° C. for 10 minutes, and thereby a polymerizationreaction was carried out. After the heating, the quartz plate wasimmersed in toluene solvent for one minute, and the quartz plate waswashed. The residual film ratio was measured from the ratio of theabsorbance (Abs) values at the absorption maximum (λmax) in the UV-visspectra obtained before and after the washing.

Residual film ratio (%)=Abs after washing/Abs before washing×100

TABLE 3 Residual film ratio (%) Oligomer 2 96.5 Oligomer 3 95.3 Oligomer4 99.4 Oligomer 5 100 Oligomer 6 98.9 Oligomer 7 96.3 Oligomer 9 92.4Oligomer 12 98.6 Oligomer 13 99.4 Oligomer 14 99.4 Oligomer 15 83.4Oligomer 18 86.6 Comparative Oligomer 1 11.2 Comparative Oligomer 2 23.1Comparative Oligomer 3 6.6

Since the oligomers according to the present invention are subjected topolymerization and insolubilization at low temperature, the oligomersare suitable for resin substrates which have low heat resistance andhigh thermal expansion. A multilayered structure can be produced on aresin substrate using the materials of the present invention, and thushigh performance organic electronic elements can be manufactured at lowcost.

<Production of Organic EL Element: Example in which Hole Transport Layeris Polymerized Layer (Organic Thin Film)>

Example 1

A PEDOT: PSS dispersion liquid (manufactured by Starck-Vtech, Ltd.,AI4083 LVW142) was spin coated at 1500 min⁻¹ on a glass substrate havingan ITO pattern with a width of 1.6 mm, and the glass substrate washeated to dry on a hot plate at 200° C. for 10 minutes in air. Thus, ahole injection layer (40 nm) was formed. The experiment thereafter wascarried out in a dry nitrogen environment.

Subsequently, a coating solution prepared by mixing the oligomer A (4.5mg) obtained as described above, a photoinitiator (0.13 mg) which wasthe ionic compound 1, and toluene (1.2 mL), was spin coated at 3000min⁻¹ on the hole injection layer, and then the coating solution wasirradiated with light (3 J/cm²) using a metal halide lamp. The coatingsolution was cured by heating on a hot plate at 180° C. for 60 minutes,and thus a hole transport layer (40 nm) was formed.

Subsequently, the glass substrate thus obtained was transferred into avacuum deposition apparatus, and CBP+Ir(piq)₃ (40 nm), BAlq (10 nm),Alq₃ (30 nm), LiF (film thickness 0.5 nm), and Al (film thickness 100nm) were deposited in this order.

After electrodes were formed, the substrate was moved into a drynitrogen environment without being exposed to the atmosphere. Thesubstrate was bonded with a sealing glass, which was an alkali-freeglass having a thickness of 0.7 mm and having a spot facing with a sizeof 0.4 mm, and an ITO substrate using a photocurable epoxy resin, andthereby the assembly was sealed. Thus, a polymer type organic EL elementhaving a multilayer structure was produced. The subsequent operation wascarried out at room temperature (25° C.) in the atmosphere.

ITO of this organic EL element was used as the positive electrode, whileAl was used as the negative electrode, and a voltage was applied to theelement. Red light emission was observed at 4 V, and the currentefficiency at a luminance of 1000 cd/m² was 5.0 cd/A. Furthermore, thecurrent voltage characteristics were measured with a micro current metermanufactured by Hewlett-Packard Development Company, L.P. 4140B, and theemission luminance was measured using a luminance meter manufactured byPhoto Research, Inc., Pritchard 1980B.

Furthermore, in regard to the lifetime characteristics, the luminancewas measured with BM-7 manufactured by Topcon Corporation, while astatic current was applied, and the time taken by the luminance todecrease by half from the initial luminance (1000 cd/m²) was measured,which was found to be 50 hours.

Comparative Example 1

An organic EL element was produced in the same manner as in Example 1,except that a hole transport layer was not formed. A voltage was appliedto this organic EL element, and red light emission was observed at 4 V.The current efficiency at a luminance of 1000 cd/m² was 4.1 cd/A, and anefficiency which was 1.2 times higher was obtained in Example 1.Furthermore, the lifetime characteristics were measured, and theluminance decreased by half in 4 hours. Thus, Example 1 had a lifetimethat was 13 times longer.

Example 2

<Production of Organic EL element: Example in which Hole Transport Layeris Polymerized Layer (Organic Thin Film) (Low Temperature Curing, HeatTreatment Only)>

An element was produced in the same manner as in Example 1, except thata coating solution prepared by mixing the oligomer 13 (4.5 mg) obtainedas described above, the initiator (the same as in Example 1) (0.45 mg),and toluene (1.2 mL) was spin coated at 3000 min⁻¹ on the hole injectionlayer, the coating solution was cured by heating on a hot plate at 120°C. for 10 minutes, and thus a hole transport layer (40 nm) was formed.ITO of this organic EL element was used as the positive electrode, whileAl was used as the negative electrode, and a voltage was applied. Redlight emission was observed at 4.0 V, and the current efficiency at aluminance of 1000 cd/m² was 5.0 cd/A. Further, the lifetimecharacteristics were measured, and the luminance decreased by half in140 hours.

<Production of Organic EL Element: Example in which Hole Injection Layeris Polymerized Layer>

Example 3

A coating solution prepared by mixing the oligomer A (4.5 mg) obtainedas described above, the photoinitiator (the same as in Example 1) (0.13mg), and toluene (500 μL) was spin coated at 3000 min⁻¹ on a glasssubstrate having an ITO pattern with a width of 1.6 mm. The operationthereafter was carried out in a dry nitrogen environment.

Subsequently, the coating solution was irradiated with light (3 J/cm²)using a metal halide lamp, and was cured by heating on a hot plate for15 minutes at 120° C. and for 60 minutes at 180° C. Thus, a holeinjection layer (40 nm) was formed.

Next, sealing was carried out in the same manner as in Example 1, whiledepositing CBP+Ir(piq)₃ (40 nm), BAlq (10 nm), Alg₃ (30 nm), LiF (filmthickness 0.5 nm), and Al (film thickness 100 nm) in this order.

ITO of this organic EL element was used as the positive electrode, whileAl was used as the negative electrode, and a voltage was applied to theelement. Red light emission was observed at 4 V, and the currentefficiency at a luminance of 1000 cd/m² was 5.5 cd/A.

Furthermore, the time taken by the luminance to decrease by half fromthe initial luminance (1000 cd/m²) was measured, which was found to be80 hours.

The efficiency was 1.3 times, and the lifetime was 20 times, as comparedwith the Comparative Example 1 in which the hole injection layer wasformed from a conventional PEDOT: PSS dispersion liquid.

Example 4

<Production of Organic EL Element: Example in which Hole Injection Layeris Polymerized Layer (Low Temperature Curing, Heat Treatment Only)>

The present Example was carried out in a dry nitrogen environment. Anelement was produced in the same manner as in Example 1, except that acoating solution prepared by mixing the oligomer 5 (4.5 mg) obtained asdescribed above, the initiator (the same as in Example 1) (0.45 mg), andtoluene (1.2 mL) was spin coated at 3000 min⁻¹ on a glass substratehaving an ITO pattern with a width of 1.6 mm, the coating solution wascured by heating on a hot plate at 120° C. for 10 minutes, and thus ahole transport layer (40 nm) was formed. ITO of this organic EL elementwas used as the positive electrode, while Al was used as the negativeelectrode, and a voltage was applied to the element. Red light emissionwas observed at 3.5 V, and the current efficiency at a luminance of 1000cd/m² was 6.0 cd/A. Furthermore, the lifetime characteristics weremeasured, and the luminance decreased by half in 250 hours.

From a comparison of Examples 1 to 4 with Comparative Example 1, it isunderstood that the organic EL elements of the Examples were superior tothe Comparative Example in terms of the emission efficiency and theemission lifetime. In this regard, it is speculated that when thepolymerized layer according to the present invention is applied as ahole injection layer or a hole transport layer, holes are efficientlyinjected and transported to the light emitting layer, and therefore, theemission efficiency is enhanced, while the emission lifetime isextended.

<Production of White Organic EL Element and Lighting Device>

Example 5

A hole injection layer (40 nm) was formed in the same manner as inExample 1 using a PEDOT: PSS dispersion liquid, while a polymerizedlayer (hole transport layer) was formed in the same manner as in Example1 using the oligomer A and the photoinitiator (the same as in Example1).

Subsequently, a mixture of CDBP (15 mg), FIr(pic) (0.9 mg), Ir(ppy)3(0.9 mg), (btp)2Ir(acac) (1.2 mg) and dichlorobenzene (0.5 mL) was spincoated at 3000 rpm under nitrogen, and subsequently the mixture wasdried for 5 minutes at 80° C. Thus, a light emitting layer (40 nm) wasformed. Furthermore, BAlq (10 nm), Alq₃ (30 nm), LiF (film thickness 0.5nm), and Al (film thickness 100 nm) were deposited in this order in thesame manner as in Example 1, and the assembly was subjected to sealing.Thus, an organic EL element and lighting device was produced.

A voltage was applied to this white organic EL element and lightingdevice, and uniform white light emission was observed.

Comparative Example 2

A white organic EL element and lighting device was produce in the samemanner as in Example 5, except that the polymerized layer was notformed.

A voltage was applied to this white organic EL element and lightingdevice. White light emission was observed, but the emission lifetime wasonly one-fourth of that of Example 5.

From a comparison between Example 5 and Comparative Example 2, it isunderstood that when the polymerized layer according to the presentinvention was inserted, a white organic EL element and a lighting devicecan be stably driven.

Example 6

(Evaluation of Polymerizability)

A coating solution prepared by mixing a toluene solution (400 μL) ofcompound 1 (4.5 mg) shown below and an ethyl acetate solution (100 μL)of ionic compound 1 (0.45 g) shown below, was spin coated on a quartzplate at 3000 rpm. Subsequently, the quartz plate was heated on a hotplate at 120° C. for 10 minutes, and thus a polymerization reaction wascarried out. After the heating, the quartz plate was immersed in a mixedsolvent of toluene : ethyl acetate (4:1) for one Minute, and the quartzplate was washed. The residual film ratio was measured from the ratio ofthe absorbance (Abs) values at the absorption maximum (λmax) in theUV-vis spectra obtained before and after washing.

Before washing: λmax=383 nm, Abs=0.229

After washing: λmax=383 nm, Abs=0.228

Residual film ratio (%)=Abs after washing/Abs beforewashing×100=0.228/0.229×100=99.6

Compound 1 (Mw=8,200, Mw/Mn=1.44, n represents an integer of 1 orgreater)

Example 7

The same procedure as in Example 6 was carried out, except that theheating temperature on the hot plate was set to 180° C., and theresidual film ratio was measured.

Example 8

The same procedure as in Example 6 was carried out, except that thefollowing ionic compound 2 was used instead of the ionic compound 1, andthe residual film ratio was measured.

Example 9

The same procedure as in Example 8 was carried out, except that theheating temperature on the hot plate was set to 180° C., and theresidual film ratio was measured.

Comparative Example 3

The same procedure as in Example 6 was carried out, except that thefollowing ionic compound 3 was used instead of the ionic compound 1, andthe residual film ratio was measured.

Comparative Example 4

The same procedure as in Comparative Example 3 was carried out, exceptthat the heating temperature on the hot plate was set to 180° C., andthe residual film ratio was measured.

Comparative Example 5

The same procedure as in Example 6 was carried out, except that thefollowing ionic compound 4 was used instead of the ionic compound 1, andthe residual film ratio was measured.

Comparative Example 6

The same procedure as in Comparative Example 5 was carried out, exceptthat the heating temperature on the hot plate was set to 180° C., andthe residual film ratio was measured.

Comparative Example 7

The same procedure as in Example 6 was carried out, except that thefollowing ionic compound 5 was used instead of the ionic compound 1, andthe residual film ratio was measured.

Comparative Example 8

The same procedure as in Comparative Example 7 was carried out, exceptthat the heating temperature on the hot plate was set to 180° C., andthe residual film ratio was measured.

The results obtained by using the various ionic compounds and evaluatingthe residual film ratios at 120° C. and 180° C. are summarized in Table4. It is understood that when the ionic compounds according to thepresent invention were used, the effect is underway at low temperature,as compared with the case of using conventional onium salt type curingagents.

TABLE 4 Residual film ratio after Residual film ratio after Item 120°C.-10 min (%) 180° C.-10 min (%) Example 6 99.6 99.6 Example 7 99.6 99.6Example 8 99.1 99.6 Example 9 99.1 99.6 Comparative 5.2 99.1 Example 3Comparative 5.2 99.1 Example 4 Comparative 0.9 12.3 Example 5Comparative 0.9 12.3 Example 6 Comparative 65.8 95.0 Example 7Comparative 65.8 95.0 Example 8

Example 10

A coating solution prepared by mixing a toluene solution (400 μL) of thecompound 1 (4.5 mg) and an ethyl acetate solution (100 μL) of the ioniccompound 1 (0.45 g), was spin coated at 3000 rpm on a glass substratehaving an ITO pattern with a width of 1.6 mm. The subsequent experimentwas carried out in a dry nitrogen environment. Subsequently, the coatingsolution was cured by heating on a hot plate at 180° C. for 10 minutes,and thus a hole injection layer (40 nm) was formed.

Subsequently, a toluene solution (1.0% by mass) of a mixture composed ofpolymer 1 (75 parts by mass), polymer 2 (20 parts by mass) and polymer 3(5 parts by mass), which are represented by the following structuralformulas, was spin coated at 3000 rpm on the hole injection layer. Thecoating solution was heated on a hot plate at 80° C. for 5 minutes, andthus a polymer light emitting layer (thickness 80 nm) was formed. Thehole injection layer and the light emitting layer could be laminatedwithout dissolving each other.

(wherein n represents an integer of 1 or greater.)

Furthermore, the glass substrate thus obtained was transferred into avacuum deposition apparatus, and electrodes were formed on the lightemitting layer using Ba (film thickness 3 nm) and Al (film thickness 100nm) in this order.

After the formation of electrodes, the substrate was moved into a drynitrogen environment without being exposed to the atmosphere, and thesubstrate was bonded with a sealing glass, which was an alkali-freeglass having a thickness of 0.7 mm and having a spot facing with a sizeof 0.4 mm, and an ITO-patterned glass substrate using a photocurableepoxy resin, and thereby the assembly was sealed. Thus, a polymer typeorganic EL element having a multilayer structure was produced. Thesubsequent experiment was carried out at room temperature (25° C.) inthe atmosphere.

ITO of this organic EL element was used as the positive electrode, whileAl was used as the negative electrode, and a voltage was applied to theelement. Green light emission was observed at about 3 V, the currentefficiency at a luminance of 5000 cd/m² was 9.1 cd/A, and the drivingvoltage was 4.9 V. Furthermore, in regard to the lifetimecharacteristics, a static current at a current density of 13 mA/cm² wasapplied, and the luminance half-life was measured, which was found to be340 hours.

Comparative Example 9

A polymer type organic EL element having a multilayer structure wasproduced in the same manner as in Example 10, except that the ioniccompound 1 was changed to the ionic compound 3. ITO of this organic ELelement was used as the positive electrode, while Al was used as thenegative electrode, and a voltage was applied to the element. Greenlight emission was observed at about 3.5 V. The current efficiency at aluminance of 5000 cd/m² was 6.9 cd/A, and the driving voltage was 5.9 V.Furthermore, in regard to the lifetime characteristics, a static currentat a current density of 14 mA/cm² was applied, and the luminancehalf-life was measured, which was found to be 70 hours. When comparedwith Example 10, the driving voltage was higher, and the luminancehalf-life was also shorter to a large extent.

DESCRIPTION OF REFERENCE NUMERALS

-   1 Light emitting layer-   2 Anode-   3 Hole injection layer-   4 Cathode-   5 Electron injection layer-   6 Hole transport layer-   7 Electron transport layer-   8 Substrate

1. An organic electroluminescent element formed by laminating at least asubstrate, an anode, a hole injection layer, a light emitting layer anda cathode, wherein the hole injection layer is a layer formed from anorganic thin film produced using an organic electronic material, whereinthe organic electronic material comprises a polymer or oligomer which(1) has at least one polymerizable substituent and (2) has a structurebranching in three or more directions, in which when a chain of saidstructure branching in three or more direction, having the highestdegree of polymerization among the various chains in one molecule of thepolymer or oligomer, is designated as the main chain, side chains havingan equal degree of polymerization or a lower degree of polymerizationare linked to the main chain, wherein the polymer or oligomer containsat least any one of the structures of the following formulas (1) to (10)as a unit serving as the starting point for forming the branchedstructure:

(wherein Ar's each independently represent a divalent linking group,each representing an arylene group or heteroarylene group having 2 to 30carbon atoms; W represents a trivalent linking group, which is an atomicgroup obtained by further excluding one hydrogen atom from the arylenegroup or the heteroarylene group and may be substituted; Y's eachindependently represent a divalent linking group; and Z represents anyone of a carbon atom, a silicon atom and a phosphorus atom).
 2. Theorganic electroluminescent element according to claim 1, wherein Y inthe formula (4) or (7) is a divalent linking group represented by one ofthe following formulas:

(wherein R's each independently represent a hydrogen atom, an optionallysubstituted, linear, cyclic or branched alkyl group having 1 to 22carbon atoms, or an optionally substituted aryl group or heteroarylgroup having 2 to 30 carbon atoms).
 3. The organic electroluminescentelement according to claim 1, wherein the polymer or oligomer containsat least one charge transporting group.
 4. The organicelectroluminescent element according to claim 1, wherein thepolymerizable substituent is introduced into an end of the polymer oroligomer.
 5. The organic electroluminescent element according to claim1, wherein three or more of the polymerizable substituents areintroduced into one molecule of the polymer or oligomer.
 6. The organicelectroluminescent element according to claim 1, wherein thepolymerizable substituent is any one of an oxetane group, an epoxygroup, a vinyl group, an acrylate group and a methacrylate group.
 7. Theorganic electroluminescent element according to claim 1, wherein thepolymer or oligomer has a partial structure represented by one of thefollowing formulas:

(wherein A₁ and A₂ each independently represent a trivalent linkinggroup; A₃ and A₄ each independently represent a tetravalent linkinggroup; L₁ to L₁₀ each independently represent adivalent linking group;X_(m) represents a divalent linking group; n represents an integer of 1or greater; and m represents 1 or an integer from 1 to n).
 8. Theorganic electroluminescent element according to claim 1, wherein thenumber average molecular weight of the polymer or oligomer is from 1,000to 1,000,000.
 9. The organic electroluminescent element according toclaim 1, wherein the polydispersity of the polymer or oligomer isgreater than 1.0.
 10. The organic electroluminescent element accordingto claim 1, further comprising a dopant.
 11. The organicelectroluminescent element according to claim 1, further comprising apolymerization initiator.
 12. The organic electroluminescent elementaccording to claim 11, wherein the polymerization initiator is a thermalpolymerization initiator.
 13. The organic electroluminescent elementaccording to claim 11, wherein the polymerization initiator is an ioniccompound.
 14. The organic electroluminescent element according to claim11, wherein the polymerization initiator also functions as a dopant. 15.Theorganic electroluminescent element according to claim 1, wherein anemission color is white.
 16. The organic electroluminescent elementaccording to claim 1, wherein the substrate is a flexible substrate. 17.The organic electroluminescent element according to claim 1, wherein thesubstrate is a resin film.
 18. A display element comprising the organicelectroluminescent element according to claim
 1. 19. A lighting devicecomprising the organic electroluminescent element according to claim 1.20. A display device comprising the lighting device according to claim19, and a liquid crystal element as a display unit.